l3 Message 2g

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PM:SBS Message Flows

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Important Notice on Product Safety DANGER - RISK OF ELECTRICAL SHOCK OR DEATH - FOLLOW ALL INSTALLATION INSTRUCTIONS. The system complies with the standard EN 60950 / IEC 60950. All equipment connected to the system must comply with the applicable safety standards. Hazardous voltages are present at the AC power supply lines in this electrical equipment. Some components may also have high operating temperatures. Failure to observe and follow all installation and safety instructions can result in serious personal injury or property damage. Therefore, only trained and qualified personnel may install and maintain the system.

The same text in German: Wichtiger Hinweis zur Produktsicherheit LEBENSGEFAHR - BEACHTEN SIE ALLE INSTALLATIONSHINWEISE. Das System entspricht den Anforderungen der EN 60950 / IEC 60950. Alle an das System angeschlossenen Geräte müssen die zutreffenden Sicherheitsbestimmungen erfüllen. In diesen Anlagen stehen die Netzversorgungsleitungen unter gefährlicher Spannung. Einige Komponenten können auch eine hohe Betriebstemperatur aufweisen. Nichtbeachtung der Installations- und Sicherheitshinweise kann zu schweren Körperverletzungen oder Sachschäden führen. Deshalb darf nur geschultes und qualifiziertes Personal das System installieren und warten.

Caution: This equipment has been tested and found to comply with EN 301489. Its class of conformity is defined in table A30808-X3247-X910-*-7618, which is shipped with each product. This class also corresponds to the limits for a Class A digital device, pursuant to part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference when the equipment is operated in a commercial environment. This equipment generates, uses and can radiate radio frequency energy and, if not installed and used in accordance with the relevant standards referenced in the manual “Guide to Documentation”, may cause harmful interference to radio communications. For system installations it is strictly required to choose all installation sites according to national and local requirements concerning construction rules and static load capacities of buildings and roofs. For all sites, in particular in residential areas it is mandatory to observe all respectively applicable electromagnetic field / force (EMF) limits. Otherwise harmful personal interference is possible.

Trademarks: All designations used in this document can be trademarks, the use of which by third parties for their own purposes could violate the rights of their owners.

Copyright (C) Siemens AG 2005. Issued by the Communications Group Hofmannstraße 51 D-81359 München Technical modifications possible. Technical specifications and features are binding only insofar as they are specifically and expressly agreed upon in a written contract.

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Reason for Update Summary: Third Edition for Release BR 8.0 Details: Chapter / Section

Reason for Update

All

Minor changes

Issue History Issue

Date of Issue

Reason for Update

1

01/2005

First Edition for New Release BR 8.0

2

04/2005

Second Edition for Release BR 8.0

3

07/2005

Third Edition for Release BR 8.0

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This document consists of a total of 236 pages. All pages are issue 3.

Contents 1 1.1 1.2 1.2.1 1.2.1.1 1.2.1.2 1.2.1.3

Performance Measurement Message Flows . . . . . . . . . . . . . . . . . . . . . . . 11 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Message Flows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Call Setup Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Successful Mobile Originating Call (MOC), FR Call . . . . . . . . . . . . . . . . . . 12 Successful Mobile Terminating Call (MTC), FR Call. . . . . . . . . . . . . . . . . . 15 Successful Mobile Originating Call (MOC) with Direct Traffic Channel Assignment, FR Call . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 1.2.1.4 Successful (MOC) Using Early Classmark Sending, FR Call . . . . . . . . . . 20 1.2.1.5 Successful Mobile Terminating Call (MTC), Using Early Classmark, Sending, FR Call . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 1.2.1.6 Successful Mobile Terminating Call (MTC) in busy mode, new waiting call (feature “Call waiting”) is accepted by called subscriber. . . . . . . . . . . . . . . 26 1.2.1.7 Unsuccessful Mobile Originating Call (MOC), Subscriber B Busy, FR Call 28 1.2.1.8 Unsuccessful Mobile Originating Call (MOC), No TCH Available, FR Call . 29 1.2.1.9 Successful Mobile Originated Call (MOC) in a Concentric Cell (inner area), FR Call . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 1.2.1.10 Successful Mobile Emergency Call (MEC), FR Call . . . . . . . . . . . . . . . . . . 32 1.2.2 Unsuccessful Assignment Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 1.2.2.1 Unsuccessful TCH Assignment Procedure with Reversion to SDCCH, FR Call 33 1.2.2.2 Unsuccessful TCH Assignment Procedure with Loss of ASSIGNMENT COMMAND (T10 < T_MSRFPCI), FR Call (T10 Expiry). . . . . . . . . . . . . . . . . . . 34 1.2.2.3 Unsuccessful TCH Assignment Procedure with Loss of ASSIGNMENT COMMAND (T10 > T_MSRFPCI), FR Call (T_MSRFPCI Expiry). . . . . . . . . . . . 35 1.2.2.4 Unsuccessful TCH Assignment Procedure LAPDm I-Frame with ASSIGNMENT COMMAND not acknowledged by MS (T200 Expiry), FR Call 36 1.2.3 Call Release Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 1.2.3.1 Normal Call Release (Originated by MS), FR Call . . . . . . . . . . . . . . . . . . . 37 1.2.3.2 Normal Call Release (Originated by Network), FR Call . . . . . . . . . . . . . . . 38 1.2.3.3 Abnormal Call Release Procedure; Call drop: BTS sends CONNECTION FAILURE INDICATION to the BSC. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 1.2.3.4 Abnormal Call Release Procedure; Call drop: BTS sends ERROR INDICATION to the BSC. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 1.2.3.5 Abnormal Call Release; BTS sends RELEASE INDICATION during a stable call phase to the BSC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 1.2.4 Inter-Cell Handover, Intra-BSC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 1.2.4.1 Successful Inter-Cell Handover, Intra-BSC, FR Call. . . . . . . . . . . . . . . . . . 45 1.2.4.2 Unsuccessful Inter-Cell Handover Attempt, Intra-BSC, No TCH Available in Target Cell, FR Call . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 1.2.4.3 Unsuccessful Inter-Cell Handover, Intra-BSC, with Reversion to Old TCH (T3124 Expiry), FR Call . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 1.2.4.4 Unsuccessful Inter-Cell Handover, Intra-BSC, with Loss of MS (Loss of HO CMD, T8
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1.2.4.5 1.2.4.6

1.2.4.7 1.2.4.8 1.2.4.9 1.2.4.10 1.2.4.11 1.2.4.12 1.2.5 1.2.5.1 1.2.5.2 1.2.5.3 1.2.5.4 1.2.5.5 1.2.5.6

1.2.5.7 1.2.5.8 1.2.5.9 1.2.5.10 1.2.6 1.2.6.1 1.2.6.2 1.2.6.3 1.2.6.4 1.2.6.5 1.2.6.6 1.2.6.7 1.2.7 1.2.7.1

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Unsuccessful Inter-Cell Handover, Intra-BSC with Loss of MS (Loss of HO CMD, T8>TTRAU), FR Call (TTRAU Expiry) . . . . . . . . . . . . . . . . . . . . . . . . 52 Unsuccessful Inter-Cell Handover, Intra-BSC, with Loss of MS, Handover Access Failure (No SABM after Transmission of PHYSICAL INFO, [(NY1+1) * T3105]<Trr7), FR Call (Trr7 Expiry) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74 Unsuccessful Inter-Cell Handover, Inter-BSC, with Loss of MS, Handover Access Failure (No SABM received after Transmission) of PHYSICAL INFO, [(NY1+1) * T3105]<TTRAU), FR Call (TTRAU Expiry) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93 Successful Intra-Cell Handover Due to Quality, MSC Controlled, FR Call . 95 Successful SDCCH-SDCCH Intra-Cell Handover . . . . . . . . . . . . . . . . . . . . 97 Directed Retry, Intra-BSC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99 Successful Directed Retry, Intra-BSC, FR Call . . . . . . . . . . . . . . . . . . . . . . 99

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1.2.7.2 1.2.7.3 1.2.7.4 1.2.7.5 1.2.7.6 1.2.8 1.2.8.1 1.2.8.2 1.2.8.3 1.2.8.4 1.2.8.5 1.2.9 1.2.9.1 1.2.9.2 1.2.9.3 1.2.10 1.2.10.1 1.2.10.2

1.2.11 1.2.11.1

1.2.11.2

1.2.11.3

1.2.11.4 1.2.11.5

1.2.11.6

1.2.11.7

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Unsuccessful Directed Retry, Intra-BSC, No Target Cell Available, FR Call . 101 Unsuccessful Directed Retry, Intra-BSC, 1 Target Cell Available, Target Cell Congested, FR Call. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102 Unsuccessful Directed Retry, Intra-BSC, with Reversion to SDCCH, FR Call (T3124 Expiry) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103 Unsuccessful Directed Retry, Intra-BSC, with Loss of MS (Loss of HO CMD, T8 < TTRAU), FR Call (T8 Expiry) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105 Unsuccessful Directed Retry, Intra-BSC, with Loss of MS (Loss of HO CMD, T8 > TTRAU), FR Call (TTRAU Expiry) . . . . . . . . . . . . . . . . . . . . . . . . . . 107 Directed Retry, Inter-BSC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109 Successful Directed Retry, Inter-BSC, FR Call . . . . . . . . . . . . . . . . . . . . . 109 Unsuccessful Directed Retry, Inter-BSC, FR Call, no Radio Resource available in Target Cell. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112 Unsuccessful Directed Retry, Inter-BSC, with Reversion to SDCCH, FR Call (T3124 Expiry) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113 Unsuccessful Derected Entry, Inter-BSC, with Loss of MS (Loss of HO CMD, T8 < Trr7), FR Call (T8 Expiry) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116 Unsuccessful Directed Retry, Inter-BSC, with Loss of MS (Loss of HO CMD, T8 > Trr7), FR Call (Trr7 Expiry) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118 Forced Handover Due to O & M . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120 Successful Forced Handover Due to O & M . . . . . . . . . . . . . . . . . . . . . . . 120 Successful Forced Handover Due to O & M, Inter-BSC, FR Call . . . . . . . 122 Successful Forced Intra-Cell Handover Due to O & M, FR Call . . . . . . . . 124 Handover due to BSS Resource Management Criteria (Traffic Handover) 125 Successful Handover due to BSS Resource Management Criteria (Traffic Handover), FR Call . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125 Unsuccessful Inter-Cell Handover due to BSS Resource Management Criteria (Traffic Handover), traffic load in Target Cell exceeds the threshold TRFLTH 128 Queuing & Preemption . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130 Queuing: Queued Assignment Request for FR TCH Is Served Before T11 Expiry, Directed Retry Enabled But No Target Cell Available, Preemption Disabled or Not Allowed for the Requesting Call . . . . . . . . . . . . . . . . . . . 130 Queuing: Queued Assignment Request for FR TCH is Discarded from the Queue Before T11 Expiry Due to an Incoming FR Assignment Request with Higher Priority Directed Retry Enabled But No Target Cell Available, Preemption Disabled or Not Allowed for the Requesting Call . . . . . . . . . . . . . . . . 132 Queuing: Queued Assignment Request for FR TCH Is Discarded from Queue Due to T11 Expiry, Directed Retry Enabled But No Target Cell Available, Preemption Disabled or Not Allowed for the Requesting Call . . . . . . . . . . . . 134 Queuing: Queued Handover Request for FR TCH Is Served Before TQHO Expiry, Preemption Disabled or Not Allowed for the Requesting Call . . . . . . 135 Queuing: Queued Handover Request for FR TCH Is Discarded from the Queue Before TQHO Expiry Due to an Incoming FR Call with Higher Priority, Preemption Disabled or Not Allowed for the Requesting Calls . . . . . . . . . 137 Queuing: Queued Handover Request for FR TCH Is Discarded from the Queue Due to TQHO Expiry, Preemption Disabled or Not Allowed for the Requesting Calls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139 Preemption: Successful Forced Inter-Cell Handover Due to Preemption, Preempted Assignment Request and Preempting Call Are Both FR . . . . . . . 140

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1.2.11.8 Preemption: Forced Release of Preempted Call Due to Lack of Target Cell for Forced Inter-Cell Handover Procedure, Preempted and Preempting Call Are Both FR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142 1.2.11.9 Preemption: Successful Forced Inter-BSC Handover Due to Preemption, Preempting Handover Request and Preempted Call Are Both FR, Originating BSC of the Preempting Handover Request and Target BSC for the Forced Handover Are the Same. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143 1.2.12 HSCSD. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145 1.2.12.1 Successful HSCSD Call, Mobile Originating, 3 TCHs Used . . . . . . . . . . . 145 1.2.12.2 Successful Inter-cell Handover of an HSCSD Call (3 TCHs Used), Intra-BSC 148 1.2.12.3 Forced Intra-cell Handover During HSCSD Assignment Procedure . . . . . 151 1.2.13 Signalling Transactions without TCH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153 1.2.13.1 Successful Location Update (Phase 2 MS) . . . . . . . . . . . . . . . . . . . . . . . . 153 1.2.13.2 Successful Location Update (2G/3G (GSM/UMTS) Multirat MS) . . . . . . . 155 1.2.13.3 Successful IMSI Detach (Phase 2 MS) . . . . . . . . . . . . . . . . . . . . . . . . . . . 157 1.2.13.4 Successful Supplementary Service (SS) Management Procedure via Subscriber-Controlled Input (SCI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158 1.2.13.5 Successful USSD (Unstructured Supplementary Service Data) Management Procedure via (SCI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 160 1.2.13.6 Unsuccessful Immediate Assignment Procedure, No SDCCH Available. . 162 1.2.13.7 Unsuccessful Immediate Assignment Procedure, No AGCH Available (AGCH Overload) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163 1.2.13.8 Unsuccessful Immediate Assignment Procedure, assigned SDCCH is not seized by the MS (Phantom RACH Scenario) . . . . . . . . . . . . . . . . . . . . . . 164 1.2.13.9 BTS Discards Invalid RACH Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . 165 1.2.13.10Immediate Assignment Procedure for Abis Link Configured via Satellite Link. 166 1.2.13.11Paging Overload - BTS discards a PAGING REQUEST Message . . . . . . 167 1.2.14 Short Message Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168 1.2.14.1 Successful SMS Mobile Originating in Idle Mode (Phase 2 MS) . . . . . . . . 168 1.2.14.2 Successful SMS Mobile Terminating in Idle Mode (Phase 2 MS) . . . . . . . 170 1.2.14.3 Successful SMS Mobile Originating in Connected Mode (FR Call Ongoing). . 172 1.2.14.4 Successful SMS Mobile Terminating in Connected Mode . . . . . . . . . . . . . 173 1.2.15 Advanced Speech Call Items (ASCI) Procedures . . . . . . . . . . . . . . . . . . . 175 1.2.15.1 VBS/VGCS Setup Initiated by fixed Dispatcher and Release . . . . . . . . . . 175 1.2.15.2 Succesful Uplink Allocation Procedure (1) . . . . . . . . . . . . . . . . . . . . . . . . . 177 1.2.15.3 FREE Uplink Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 179 1.2.15.4 VGCS Setup initiated by Service Subscriber and Release . . . . . . . . . . . . 180 1.2.15.5 VGCS SETUP initiated by Service Subscriber (FAST CALL SETUP) . . . . 183 1.2.15.6 MTC During Ongoing VBS/VGCS Connection. . . . . . . . . . . . . . . . . . . . . . 184 1.2.15.7 VBS/VGCS Call during Ongoing Speech Call . . . . . . . . . . . . . . . . . . . . . . 185 1.2.16 Inter System Handover (2G <--> 3G), circuit switched (CS) . . . . . . . . . . . 186 1.2.16.1 Successful Inter System Handover (2G --> 3G) . . . . . . . . . . . . . . . . . . . . 186 1.2.16.2 Unsuccessful Inter System Handover (2G --> 3G), loss of MS (loss of HOCMD), T3121 expiry . . . . . . . . . . . . . . . . . . . . . . . . 188 1.2.16.3 Unsuccessful Inter System Handover (2G --> 3G), No TCH available in Target UMTS Cell (3G) . . . . . . . . . . . . . . . . . . . . . . . 190

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1.2.16.4 Unsuccessful Inter System Handover (2G --> 3G), Revision to old TCH, T3124 expiry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 191 1.2.16.5 Successful Inter System Handover (3G --> 2G) . . . . . . . . . . . . . . . . . . . 192 1.2.16.6 Unsuccessful Inter System Handover (3G --> 2G), No TCH available in Target GSM Cell (2G) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 194 1.2.17 Inter System Cell Reselection Procedure (2G <--> 3G), packet oriented (PO), intra SGSN inter system change. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195 1.2.17.1 Successful Inter System Cell Reselection Procedure (2G --> 3G) . . . . . . 195 1.2.17.2 Successful Inter System Cell Reselection Procedure (3G --> 2G) . . . . . . 198 1.2.18 Other Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 202 1.2.18.1 Idle Traffic Channel Supervision . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 202 1.2.18.2 Uplink and Downlink Measurement Reports on Abis . . . . . . . . . . . . . . . . 203 1.2.18.3 IMSI Trace Invocation for Normal Call Setup . . . . . . . . . . . . . . . . . . . . . . 204 1.2.18.4 IMSI Trace Invocation for Incoming Inter-BSC Handover . . . . . . . . . . . . . 205 1.3 GPRS Message Flows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206 1.3.1 GPRS Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206 1.3.1.1 GPRS Mobility Management: Attach Procedure. . . . . . . . . . . . . . . . . . . . 206 1.3.1.2 GPRS Mobility Management: Detach Procedure . . . . . . . . . . . . . . . . . . . 207 1.3.1.3 GPRS Session Management: Activate PDP Context . . . . . . . . . . . . . . . . 208 1.3.1.4 GPRS Session Management: Deactivate PDP Context . . . . . . . . . . . . . . 209 1.3.1.5 GPRS: Paging. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209 1.3.1.6 GPRS Mobility Management: Routing Area Update . . . . . . . . . . . . . . . . . 210 1.3.1.7 GPRS Mobility Management: Cell Update . . . . . . . . . . . . . . . . . . . . . . . . 212 1.3.1.8 GPRS: Suspend / Resume . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213 1.3.2 LC/MAC Message Flows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215 1.3.2.1 Uplink TBF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 216 1.3.2.2 Downlink TBF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 220 1.3.2.3 Concurrent UL TBF. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 223 1.3.2.4 Concurrent DL TBF. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 226 2

Counter / Message Abbreviations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 229

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Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 235

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1 Performance Measurement Message Flows 1.1

Introduction The following sections show the SBS-specific message flows of call- and signallingtransactions on the interfaces Um, Abis and A.

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Note: The message flows have to be considered as typical examples for the affected signalling transactions. Depending on specific settings in the involved network elements (MSC, BSC), flow traces taken from ’real live’ networks can deviate from the shown message flows (especially for the optional sub-procedures Authentication, Ciphering, Early Classmark Sending and TMSI Reallocation). The messages between the network elements (MS, BTS, BSC and MSC) are abbreviated in the same way as the most common protocol analyzers (e.g. K1103, K1205, etc.) do. For the mapping of the used abbreviations to the complete message names defined by GSM and the Siemens Abis specifications please refer to Chapter 2 “Abbreviations”. In addition to the messages, the implemented SBS performance measurement counters are embedded into the message flows in such a way that the association of the counters to their triggering events becomes clear. As a general rule, the appearance of a counter within a message flow means that its value is increased by ’1’. Deviations from this rule are explicitely mentioned in the message flows. To indicate also the subcounters of the specific measurements, the following method is used: (.). Example: “ATINHIRC (2.)” means that the second subcounter of the measurement ATINHIRC (’downlink quality’) is increased by the marked event. For the long names of the measurements, please refer to the document “PM:SBS Counter”.

i

i

Note: If not otherwise defined the blue colour generally indicates the events on the handover target resources. In 1.2.11.2 the blue colour indicates the events related to the second (high priority) call. In 1.2.11.5 the blue colour indicates the events related to the high priority call. In 1.2.11.7, 1.2.11.8 and 1.2.11.9 the blue colour indicates the events related to preempting call. In 1.2.5.7 the red colour indicates the BSC serving the first (really external) target cell in the target cell list of the HANDOVER REQUIRED message. SMLC-Specific Message Flows: In order to guarantee an SBS release-independent documenation delivery, the SMLCrelated message flows are provided in a separate documentation set. The manual PM:SBS Message Flows is intended for the SBS-specific message flows, whereas the manual PM:SMLC Message Flows is intended for the SMLC-specific message flows. Both manuals may be used together, if applicable.

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11


1.2 1.2.1 1.2.1.1

Information System

Message Flows Call Setup Procedures Successful Mobile Originating Call (MOC), FR Call

MS

BTS

BSC

CHNREQ

MSC

CHNRD

RACH

NATTSDPE NACSUCPR (3.) ATIMASCA (4.) If last SDCCH start ASDCALTI CHNAV (SDCCH) CHNAK Start T_MSRFPCI IACMD (IMASS)

UI (IMASS)

Start T3101

AGCH

NTDMAGCH (1.)

SABM (CMSREQ)

TACCBPRO (2.) SUIMASCA (4.) NACSUCPR (2.)

ESTIN (CMSREQ)

SDCCH

Start T3101 NSUCCHPC (4.) NASUSDPE

UA SDCCH

CR (CL3I; CMSREQ)

MRPCI Stop T_MSRFPCI DATRQ (AUTREQ)

I (AUTREQ)

CC (AUTREQ)

SDCCH

I (AUTREP) DATIN (AUTREP)

SDCCH

ENCRY (CIMCMD)

I (CIMCMD) I (CIMCMP) SDCCH

12

DT1 (AUTREP) DT1 (CICMD)

SDCCH

DATIN (CIMCMP)

DT1 (CICMP)

A30808-X3247-M41-3-7618

Information System


MS

BTS SETUP

BSC DATIN (SETUP)

SDCCH

DT1 (SETUP) DT1 (CPROC)

DATRQ (CPROC)

I (CPROC)

MSC

SDCCH

DT1 (ASS REQ) ATTCHSEI (1.) TASSATT (2.) If last TCH start AALTCHTI (1.) PHCRQ PHCCN

MTCHBUTI (1.) (start)

CHNAV (TCH) Start TTRAU

CHNAK

Start T_MSRFPCI DATRQ (ASS CMD) I (ASS CMD)

Start T10

Stop TTRAU (**) SDCCH

SABM ESTIN

FACCH

UA TNTCHCL (1.)

FACCH

I (ASS CMP) FACCH

DATIN (ASS CMP) Stop T10

MRPCI

DT1 (ASS COM)

SUCTCHSE (1.) TASSSUCC (2.)

Stop T_MSRFPCI RELRQ RELCN RCHRL (SDCCH) RCHRA ASDCALTI (stop) MBUSYSSP (1.) (accumulation)

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13


MS

Information System

BTS

BSC

MSC called party is reachable and idle (’ringing’) DT1 (ALERT)

DATRQ (ALERT)

I (ALERT)

called party has accepted the call

FACCH

DT1 (CONNECT) DATRQ (CONNECT)

I (CONNECT) FACCH

I (CONACK) FACCH

DATIN (CONACK)

DT1 (CONACK)

Conversation phase ...

(**)

14

TTRAU is stopped when the BTS receives the (idle) TRAU frames from the TRAU. This happens when the BSC throughconnects the Asub-TCH to the Abis-TCH. In case of TCH Assignment this is done on transmission of the ASSIGNMENT COMMAND.

A30808-X3247-M41-3-7618

Information System


1.2.1.2

Successful Mobile Terminating Call (MTC), FR Call

MS

BTS

BSC

MSC UDT (PAGIN)

PGCMD UI (PAGREQ) PCH

CHNREQ

TACCBPRO (1.)

NTDMPCH (1.)

CHNRD

RACH

NATTSDPE NACSUCPR (1.), (3.) ATIMASCA (1.) If last SDCCH start ASDCALTI

CHNAV (SDCCH) CHNAK Start T_MSRFPCI

IACMD (IMASS)

UI (IMASS)

Start T3101

AGCH

NTDMAGCH (1.)


SABM (PAGRES)

ESTIN (PAGRES)

SDCCH

Stop T3101

UA

NSUCCHPC (1.) NASUSDPE

SDCCH

(CL3L; PAGRES)

MRPCI Stop T_MSRFPCI

Optional: Authentication & Ciphering Procedure... (see 1.2.1.1)

DATRQ (TRCMD)

I (TRCMD) SDCCH

DATIN (SETUP)

I SETUP I (TRCMP)

SDCCH

DATIN (TRCMP)

SDCCH

I (CCONF) SDCCH

A30808-X3247-M41-3-7618

DATRQ (CCONF)

DT1 (TRCMD) DT1 (SETUP)

DT1 (TRCMP) DT1 (CCONF)

15


MS

Information System

BTS

BSC

MSC

DT1 (ASREQ) ATTCHSEI (1.) TASSATT (2.) If last TCH start AALTCHTI (1.) PHCRQ MTCHBUTI (1.) (start) PHCCN CHNAV (TCH) Start TTRAU

CHNAK

Start T_MSRFPCI DATRQ (ASS CMD) Start T10

Stop TTRAU (**) I (ASS CMD) SDCCH

SABM FACCH

ESTIN

UA TNTCHCL (1.)

FACCH

I (ASS CMP) FACCH


MRPCI

DT1 (ASS COM)



16

A30808-X3247-M41-3-7618

Information System


MS

BTS

BSC

MSC

called MS is ready (’ringing’) I (ALERT)

DATIN (ALERT)

FACCH

DT1 (ALERT)

called MS has accepted the call I (CONNECT)

DATIN (CONNECT)

FACCH

DATRQ (CONACK)

I (CONACK)

DT1 (CONNECT) DT1 (CONACK)

FACCH


(**)


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17


1.2.1.3

Information System

Successful Mobile Originating Call (MOC) with Direct Traffic Channel Assignment, FR Call

MS

BTS CHNREQ

BSC

MSC

CHNRD

RACH

ATTCHSEI (1.) ATIMASCA (4.) NASCUCPR (3.) If last TCH start AALTCHTI (1.) CHNAV (TCH) Start TTRAU

MTCHBUTI (1.) (start) CHNAK

Start T_MSRFPCI IACMD (IMASS) UI (IMASS) Start T3101

AGCH


NTDMAGCH (1.)

SABM (CMSREQ) ESTIN (CMSREQ)

FACCH

Stop T3101 UA

Stop TTRAU (**)

NSUCCHPC (10.) SUCTCHSE (1.) TNTCHCL (1.)

FACCH

MRPCI

CR (CL3I;CMSREQ)

Stop T_MSRFPCI

Optional: Authentication & Ciphering Procedure...(see 1.2.1.1) I (SETUP)

DATIN (SETUP)

FACCH

DT1 (SETUP) DATRQ (CPROC)

DT1 (CPROC)

I (CPROC) FACCH

18

A30808-X3247-M41-3-7618

Information System


MS

BTS

BSC

MSC

DT1 (ASS REQ) TASSATT (2.) MOMRQ MOMAK DATRQ (CHMM)

I (CHMM)

(***)

FACCH

I (CHMMACK) FACCH

DATIN (CHMMACK) DT1 (ASS COM) called party is reachable and idle (’ringing’)

TASSSUCC (2.)

DATRQ (ALERT)

I (ALERT)


FACCH

DATRQ (CONNECT)

I (CONNECT) I (CONACK) FACCH

DT1 (ALERT)

DT1 (CONNECT)

FACCH

DATIN (CONACK)

DT1 (CONACK)


(**)


(***)

In case of direct TCH assignment the timer T10 is not used. Two not-administrable system internal timers are used, one for the control of the MOMRQ procedure, one for the control of the CHMM procedure. In case of expiry of one of these timers, the BSC sends an ASS FAI with cause ’equipment failure’ to the MSC.

A30808-X3247-M41-3-7618

19


1.2.1.4

Information System

Successful (MOC) Using Early Classmark Sending, FR Call

MS

BTS CHNREQ

BSC

MSC

CHNRD

RACH

NATTSDPE NACSUCPR (3.) ATIMASCA (4.) If last SDCCH start ASDCALTI CHNAV (SDCCH) CHNAK Start T_MSRFPCI IACMD (IMASS) Start T3101

UI (IMASS) AGCH

NTDMAGCH (1.) I (CMSREQ)


ESTIN (CMSREQ)

SDCCH

Stop T3101 NSUCCHPC (4.) NASUSDPE MRPCI

ENCRY (CIMCMD)

I (CIMCMD)

CR (CL3I; CMSREQ)

CC (CICMD)

SDCCH

I (CLAMCH)

DATIN (CLAMCH)

SDCCH

MRPCI

DT1 (CLUPD)

Stop T_MSRFPCI I (CIMCMP)

DATIN (CIMCMP)

SDCCH

DATRQ (TRCMD)

I (TRCMD)

DT1 (CICMP) DT1 (TRCMD)

SDCCH

I (SETUP)

DATIN (SETUP)

SDCCH

DATRQ (CPROC)

I (CPROC)


SDCCH

20

A30808-X3247-M41-3-7618

Information System


MS

BTS

BSC

MSC DT1 (ASREQ)

ATTCHSEI TASSATT (5.) If last TCH start AALTCHTI (1.) PHCRQ PHCCN



CHNAK


Start T10


I (TRCMP)

DATIN (TRCMP)

SDCCH

SABM

DT1 (TRCMP)

ESTIN

FACCH

UA

TNTCHCL (1.) FACCH

I (ASS CMP) FACCH


MRPCI

DT1 (ASS COM)



A30808-X3247-M41-3-7618

21


MS

Information System

BTS

BSC

MSC called party is reachable and idle (’ringing’) DT1 (ALERT)

DATRQ (ALERT) I (ALERT) FACCH

Call setup continuation...

(**)

22


A30808-X3247-M41-3-7618

Information System


1.2.1.5

Successful Mobile Terminating Call (MTC), Using Early Classmark, Sending, FR Call

MS

BTS

BSC

MSC UDT (PAGIN)

PGCMD UI (PAGREQ) PCH

CHNREQ

TACCBPRO (1.)

CHNRD

RACH

NATTSDPE NACSUCPR (1.), (3.) ATIMASCA (1.) If last SDCCH start ASDCALTI

CHNAV (SDCCH) CHNAK Start T_MSRFPCI

IACMD (IMASS)

UI (IMASS)

Start T3101

AGCH

NTDMAGCH (1.)


SABM (PAGRES)

ESTIN (PAGRES)

SDCCH

Stop T3101

UA


SDCCH

CR (CL3I; PAGRES)

ENCRY (CIMCMD)

I (CIMCMD) I (CLAMCH) SDCCH

CC (CIMCMD)

SDCCH

DATIN (CLAMCH)

DT1 (CLUPD)


I (CIMCMP) SDCCH

A30808-X3247-M41-3-7618

DATIN (CIMCMP)

DT1 (CICMP)

23


MS

Information System

BTS

I (TRCMD) SDCCH

BSC

DT1 (TRCMD)

DATRQ (TRCMD)

DT1 (SETUP)

DATIN (SETUP)

I SETUP

MSC

SDCCH SDCCH

I (TRCMP)

DATIN (TRCMP)

DT1 (TRCMP)

I CCONF

DATRQ (CCONF)

DT1 (CCONF)

SDCCH

DT1 (ASREQ) ATTCHSEI (1.) TASSATT (2.) If last TCH start AALTCHTI (1.) PHCRQ MTCHBUTI (1.) (start) PHCCN CHNAV (TCH) Start TTRAU

CHNAK



SABM FACCH

ESTIN

UA TNTCHCL (1.)

FACCH

I (ASS CMP) FACCH


MRPCI

DT1 (ASS COM)


Stop T_MSRFPCI

24

A30808-X3247-M41-3-7618

Information System


BSC

BTS

MS

MSC

RELRQ RELCN RCHRL (SDCCH) RCHRA ASDCALTI (stop) MBUSYSSP (1.) (accumulation) DATRO (ALERT)

I (ALERT)

DT1 (ALERT)

FACCH

Call setup continuation...

(**)


A30808-X3247-M41-3-7618

25


1.2.1.6

Information System

Successful Mobile Terminating Call (MTC) in busy mode, new waiting call (feature “Call waiting”) is accepted by called subscriber

MS

BTS

MSC

BSC

called party is reachable and idle (’ringing’) DT1 (ALERT) DATRQ (ALERT)

I (ALERT)


FACCH

DATRQ (CONNECT)

I (CONNECT)

DT1 (CONNECT)

FACCH

I (CONACK)

DATIN (CONACK)

FACCH

DT1 (CONACK)

Conversation phase ... new call for a busy subscriber arrives at MS DATIN (SETUP)

I SETUP)*

DT1 (SETUP)*

SDCCH

I (CCONF)* SDCCH

DATRQ (CCONF)*

(cause: user busy

DATRQ (ALERT)*

I (ALERT)*

DT1 (CCONF)* DT1 (ALERT)*

FACCH

called subscriber accepts new cell and releases the old one by the pressing the appropriate keys on the MS I (STDTMF) FACCH

DATRQ (STDTMF)

DT1 (STDTMF)

DATIN (STDACK)

DT1 (STDACK)

I (STDACK) FACCH

I (SPDTMF)

DATRQ (SPDTMF)

FACCH

I (SPDACK)

26

FACCH

DATIN (SPDACK)

DT1 (SPDTMF) DT1 (SPDACK)

A30808-X3247-M41-3-7618

Information System


MS

BTS

BSC

MSC

I (DISC) FACCH (cause: normal call clearing)

DATIN (DISC)

DATIN (RELEAS) I (RELEAS)

DT1 (DISC) DT1 (RELEAS) (cause: normal call clearing)

FACCH

I (RELCMP) DATIN (REL CMP)

FACCH

I (CONNECT)*

DATIN (CONNECT)*

FACCH

DATIN (CONACK)*

DT1 (REL CMP)

DT1 (CONNECT)* DT1 (CONACK)*

I (CONACK)* FACCH

Conversation phase of new accepted call...

(*)

Messages related to new waiting and accepted call.

A30808-X3247-M41-3-7618

27


1.2.1.7

Information System

Unsuccessful Mobile Originating Call (MOC), Subscriber B Busy, FR Call

MS

BTS

BSC

MSC

Call setup ... (see Successful MOC) I (ASS CMP)

DATIN (ASS CMP)

FACCH

Stop T10

MRPCI

DT1 (ASS COM)


Stop T_MSRFPCI RELRQ RELCN RCHRL (SDCCH) RCHRA ASDCALTI (stop) MBUSYSSP (1.) (accumulation) DATRQ (DISC)

I (DISC)

DT1 (DISC) (cause: user busy)

SDCCH

Call release... (see ‚normal call release, originated by network‘)

28

A30808-X3247-M41-3-7618

Information System


1.2.1.8

Unsuccessful Mobile Originating Call (MOC), No TCH Available, FR Call

MS

BTS

BSC

MSC

Call setup ...

I (SETUP)

DATIN (SETUP)

SDCCH


DATRQ (CPROC)

I (CPROC)

DT1 (ASS REQ)

SDCCH

ATTCHSEI (1.) ATCHSMBS (1.) TASSATT (2.)

DT1 (ASS FAI)

(cause: no radio resource available)

TASSFAIL (8.) DATRQ (DISC)

I (DISC)

DT1 (DISC)

(cause: no circuit/channel available)

FACCH

Call release ... (see ‚Normal call release, originated by network‘)

A30808-X3247-M41-3-7618

29


1.2.1.9

Information System

Successful Mobile Originated Call (MOC) in a Concentric Cell (inner area), FR Call

MS

BTS

BSC

MSC

Call setup ... I (SETUP)

DATIN (SETUP)

SDCCH


DATRQ (CPROC)

I (CPROC)

DT1 (ASS REQ)

SDCCH

PAREQ

ATTCHSEI (1.) TASSATT (2.) If last TCH start AALTCHTI (1.)

PAREA (preferred area type: inner area)

PHCRQ PHCCN


CHNAV (TCH) Start TTRAU CHNAK Start T_MSRFPCI DATRQ (ASS CMD) Start T10


SABM FACCH

ESTIN UA FACCH

I (ASS CMP) FACCH

TNTCHCL (1.) (for concentric cells) DATIN (ASS CMP) Stop T10 DT1 (ASS COM) SUCTCHSE (1.) TASSSUCC (2.)

30

A30808-X3247-M41-3-7618

Information System


MS

BTS

BSC

MSC

MRPCI Stop T_MSRFPCI RELRQ RELCN RCHRL (SDCCH) RCHRA AALTCHTI (1.) (stop) MTCHBUTI (1.)(stop) MBUSYSSP (1.) (accumulation) DT1 (ALERT) DATRQ (ALERT)

I (ALERT) FACCH

Call setup continuation ...

(**)


A30808-X3247-M41-3-7618

31


1.2.1.10

Information System

Successful Mobile Emergency Call (MEC), FR Call

MS

BTS CHNREQ

RACH

(request reference: emergency call)

BSC

MSC

CHNRD NATTSDPE NACSUCPR (3.) ATIMASCA (2.) If last SDCCH start ASDCALTI CHNAV (SDCCH) CHNAK

Start T_MSRFPCI IACMD (IMASS)

UI (IMASS)

Start T3101

AGCH

NTDMAGCH (1.)

TACCBPRO () (2.) SUIMASCA (2.) NACSUCPR (2.)

SABM (CMSREQ) SDCCH (CM service type: emergency call establishment)

ESTIN (CMSREQ) Stop T3101 NSUCCHPC (2.) NASUSDPE

UA SDCCH

CR (CL3I; CMSREQ)


Optional: Authentication & Ciphering Procedure (see 1.2.1.1) I (EMSETUP)

DATIN (EMSETUP)

SDCCH

DATRQ (CPROC)

I (CPROC)

DT1 (EMSETUP) DT1 (CPROC) DT1 (ASREQ)

SDCCH

ATTCHSEI (1.) TASSATT (2.) If last TCH start AALTCHTI (1.)

Call setup continuation ...

32

A30808-X3247-M41-3-7618

Information System


1.2.2 1.2.2.1

Unsuccessful Assignment Procedures Unsuccessful TCH Assignment Procedure with Reversion to SDCCH, FR Call

MS

BTS

BSC

MSC

Call setup ... DT1 (ASS REQ)

PHCRQ

ATTCHSEI (1.) TASSATT (2.) If last TCH start AALTCHTI MTCHBUTI (1.) (start)

PHCCN CHNAV (TCH) Start TTRAU

CHNAK

Start T_MSRFPCI DATRQ (ASS CMD) I (ASS CMD) Start T10

SDCCH

SABM FACCH

SABM FACCH

SABM FACCH

Access to target channel fails...

.... SABM

ESTIN

SDCCH

UA SDCCH

I (ASS FAIL) SDCCH

DATIN (ASS FAIL)

(Cause: protocol error unspecified)

Stop T10 TASSFAIL (7.)

DATRQ (DISC)

I (DISC)

DT1 (ASS FAIL) (cause: radio interface failure, reversion to old channel)

DT1 (DISC) (cause: normal, unspecified)

SDCCH

Call release ...

A30808-X3247-M41-3-7618

33


1.2.2.2

Information System

Unsuccessful TCH Assignment Procedure with Loss of ASSIGNMENT COMMAND (T10 < T_MSRFPCI), FR Call (T10 Expiry)

MS

BTS

BSC

MSC

Call setup ... DT1 (ASS REQ) ATTCHSEI (1.) TASSATT (2.) If last TCH start AALTCHTI PHCRQ MTCHBUTI (1.) (start)

PHCCN

CHNAV (TCH) Start TTRAU CHNAK Start T_MSRFPCI DATRQ (ASS CMD) I (ASS CMD)

Stop TTRAU (**)

Start T10

SDCCH

ASS CMD is lost ... Expiry T10

DT1 (ASS FAI)

(cause: radio interface msg failure)

TASSFAIL (6.) DT1 (CL CMD) (cause: call control)

Release of resources ...

(**)

34


A30808-X3247-M41-3-7618

Information System


1.2.2.3

Unsuccessful TCH Assignment Procedure with Loss of ASSIGNMENT COMMAND (T10 > T_MSRFPCI), FR Call (T_MSRFPCI Expiry)

MS

BTS

BSC

MSC

Call setup ... DT1 (ASS REQ) ATTCHSEI (1.) TASSATT (2.) If last TCH start AALTCHTI PHCRQ PHCCN


CHNAV (TCH) Start TTRAU CHNAK Start T_MSRFPCI DATRQ (ASS CMD) I (ASS CMD)

Start T10


ASS CMD is lost ...

Expiry T_MSRFPCI

CONFL

(cause: T_MSRFPCI expired)

NRFLTCH (4.)

DT1 (CL REQ)


DT1 (CL CMD) (cause: radio interface msg failure)

Release of resources ...

(**)


A30808-X3247-M41-3-7618

35


1.2.2.4

Information System

Unsuccessful TCH Assignment Procedure LAPDm I-Frame with ASSIGNMENT COMMAND not acknowledged by MS (T200 Expiry), FR Call

MS

BTS

BSC

MSC

Call setup ... DT1 (ASS REQ) ATTCHSEI (1.) TASSATT (2.) If last TCH start AALTCHTI (1.)

PHCRQ PHCCN



CHNAK


Stop TTRAU (**) I (ASS CMD) I (ASS CMD)

SDCCH SDCCH

I (ASS CMD)

T200 T200 T200 expired N200+1 times))

SDCCH

I (ASS CMD) SDCCH

T200

ERRIN (cause: timer T200 expired N200+1 times))

NRFLSDCC (1.) DT1 (CL REQ) (cause: radio interface msg failure)

NRCLRREQ (3.)

DT1 (CL CMD)


NRCLRCMD (1.)

Release of resources ... (**)

36


A30808-X3247-M41-3-7618

Information System


1.2.3 1.2.3.1

Call Release Procedures Normal Call Release (Originated by MS), FR Call

MS

BTS

BSC

MSC

Conversation phase ... I (DISC) FACCH (cause: normal call clearing)

DATIN (DISC)

DT1 (DISC)

DT1 (RELEAS)

DATRQ (RELEAS)

(cause: normal call clearing)

I (RELEAS) FACCH

I (RELCMP)

DATIN (REL CMP)

FACCH

DT1 (REL CMP) DT1 (CL CMD) (cause: call control)

NRCLRCMD (2.) DATRQ (CHREL)

I (CHREL)

Start T3109

FACCH

Start T3110

DT1 (CL CMP)

DESAC DISC

RELIN

FACCH

UA Stop T3110

RLSD (cause: end user originated)

Stop T3109

FACCH

Start T3111 RLC RCHRL (TCH)

Expiry T3111

RCHRA MTCHBUTI (1.) (stop) AALTCHTI (1.) (stop)

A30808-X3247-M41-3-7618

37


1.2.3.2

Information System

Normal Call Release (Originated by Network), FR Call

MS

BTS

BSC

MSC

Conversation phase ... DT1 (DISC)

DATIN (DISC)

I (DISC)

(cause: normal call clearing)

FACCH

I (RELEAS) FACCH (cause: normal call clearing)

DATRQ (RELEAS)

DT1 (RELEAS) DT1 (REL CMP)

DATIN (REL CMP)

I (RELCMP)

DT1 (CL CMD)

FACCH

(cause: call control)

NRCLRCMD (2.)

Start T3109

FACCH

Start T3110

DESAC DISC

RELIN

FACCH

UA Stop T3110

DT1 (CL CMP)

DATRQ (CHREL)

I (CHREL)

RLSD (cause: end user originated)

Stop T3109 FACCH

Start T3111 RLC

RCHRL (TCH)

Expiry T3111


38

A30808-X3247-M41-3-7618

Information System


1.2.3.3

Abnormal Call Release Procedure; Call drop: BTS sends CONNECTION FAILURE INDICATION to the BSC

MS

BTS

BSC

MSC

Call or dedicated connection (SDCCH or FACCH) established... Radio link counter in the BTS (RDLNKTBS**) reaches “0” CONFL (cause: radio link failure)

NRFLTCH (7.) or * NRFLSDCC (7.)

or... TTRAU expiry*** or TSYNC/TSYNCDL**** expiry

CONFL (cause: remote transcoder failure)


or...

T_MSRFPCI expiry*****

CONFL (cause: T_MSRFPCI expired)


A30808-X3247-M41-3-7618

39


MS

Information System

BTS

BSC

MSC

or... MS-BTS distance exceeds the threshold EXCDIST

CONFL (cause: distance limit exceeded******)

NRFLTCH (5.) or * NRFLSDCC (5.) DT1 (CL REQ) NRCLRREQ (3.)

(cause: radio interface message failure******)

NRCLRREQ (3.) or NRCLRREQ (6.)******

DT1 (CL CMD) NRCLRCMD (1.) RELRQ

DT1 (CL CMP)

RELCN RCHRL (New TCH) Reset T_MSRFPCI RCHRA MTCHBUTI (1.) (stop)

40

A30808-X3247-M41-3-7618

Information System


(*)

If the CONNECTION FAILURE INDICATION is received a TCH, NRFLTCH is triggered; if it is received for an SDCCH, NRFLSDCC is triggered.

(**)

RDLNKTBS is the initial value of the 'S' Counter. This counter in the BTS is decreased by '1' if the BTS cannot decode a SACCH frame correctly. When the BTs can decode a SACCH frame again, RDLNKTBS is increased by '2'. If the counter reaches '0', the Um connection is regarded as lost.

(***)

TTRAU is started in the BTS on receipt of the CHANNEL ACTIVATION message for a TCH. Its purpose is to observe the receipt of TRAU frames from the TRAU after the activation of the TCH, i.e. it is stopped when TRAU frames are received.

(****)

TSYNC is started in the BTS when the BTS does not receive valid TRAU frames for an activated TCH anymore. Its purpose is to observe the re-appearance of TRAU frames from the TRAU, i.e. it is stopped again when TRAU frames are received. TSYNC is used for FR, HR and EFR speech calls and for standard dataservices (up to 9,6 kbit/s). For AMR calls and 14,4 kbit/s dataservices TSYNC is replaced by TSYNCDL.

(*****)

T_MSRFPCI is started in the BTS on receipt of the CHANNEL ACTIVATION ACKNOWLEDGE message for a TCH. Its purpose is to observe the receipt of the MPRCI message, i.e. it is stopped when the MRPCI message is received. The BSC sends this message when the MS has successfully sent the first layer 3 message on a new channel during call setup (CM SERVICE REQUEST (for the SDCCH) and ASSIGNMENT COMPLETE) and handover (ASSIGNMENT COMPLETE (intracell HO) and HANDOVER COMPLETE (inter-cell handover)). As T_MSRFPCI is hardcoded to a very long value (20s), this timer should never expire under normal conditions and reasonable timer settings.

(******) When the BSC receives a CONNECTION FAILURE INDICATION with cause ’distance limit exceeded’, the cause value contained in the CLEAR REQUEST message will not be ’radio interface message failure’ but ’distance’. Consequently also the corresponding NRCLRREQ subcounter (6.) is triggered instead of subcounter (3.).

A30808-X3247-M41-3-7618

41


1.2.3.4

MS

Information System

Abnormal Call Release Procedure; Call drop: BTS sends ERROR INDICATION to the BSC

BTS

BSC

MSC

Call or dedicated connection (SDCCH or FACCH) established... BTS has sent a Um layer 2 (LAPDm) message in ’acknowledged mode’ N200+1 times to the MS without receiving an appropriate layer 2 acknowledgement. ERRIN (cause: timer T200 expired N200+1 times)


RELIN**

or... MS has sent a Um layer 2 (LAPDm) message DM (Mode) to the BTS while the BTS-MS communication is in ’multiple frame stablished state’

DM FACCH or SDCCH

ERRIN (cause: unsolicited DM response, multiple frame established state)


RELIN**

42

A30808-X3247-M41-3-7618

Information System

MS


BTS

BSC

MSC

or... BTS has detected irregularities in the Um layer 2 (LAPDm) flow control functions (wrong message sequence) useds in ’acknowledged mode’ ERRIN (cause: sequence error)

NRFLTCH (3.) or * NRFLSDCC (3.) RELIN** DT1 (CL REQ) NRCLRREQ (3.)

(cause: radio interface message failure)

DT1 (CL CMD) NRCLRCMD (1.) RCHRL (New TCH)

DT1 (CL CMP)

Reset T_MSRFPCI RCHRA MTCHBUTI (1.) (stop)

(*)

If the ERROR INDICATION is received for a TCH, NRFLTCH is triggered; if it is received for a SDCCH, NRFLSDCC is triggered.

(**)

The RELEASE INDICATION is always sent directly after the ERROR INDICATION to indicate that the layer 2 context on the Um interface has already been cleared by the BTS.

A30808-X3247-M41-3-7618

43


1.2.3.5

Information System

Abnormal Call Release; BTS sends RELEASE INDICATION during a stable call phase to the BSC

MS

BTS

BSC

MSC

Call or dedicated TCH connection in a stable phase... Due to MS-internal irregularities, the MS disconnects the layer 2 on the Um interface.

DISC RELIN DT1 (CL REQ) (cause: radio interface failure)

NRCLRREQ (2.)

DT1 (CL CMD) NRCLRCMD (1.) RELRQ RELCN RCHRL (New TCH) Reset T_MSRFPCI RCHRA MTCHBUTI (1.) (stop)

44

A30808-X3247-M41-3-7618

Information System


1.2.4

Inter-Cell Handover, Intra-BSC

1.2.4.1

Successful Inter-Cell Handover, Intra-BSC, FR Call

BTSold

MS

BTSnew

BSC

MSC

Call in progress... UI (MEAS REP) SACCH

UI (MEAS REP) SACCH

UI (MEAS REP)

BWHCI

SACCH

Start THORQST

(with HO cause)

ATTCHSEI (1.) ATINHIRC (*) If last TCH start AALTCHTI (1.) CHNAV (New TCH) Start TTRAU


Start T_MSRFPCI DATRQ (HO CMD) I (HO CMD)

Start T8

FACCH

HO ACCESS

AININIRH (*) AOUINIRH (*)

FACCH

Start T3124

HO ACCESS HANDO

FACCH

UI (PHYS INFO)

Stop TTRAU (**) FACCH

Stop T3124 Start T3105 SABM FACCH

Stop T3105 ESTIN

UA FACCH

TNTCHCL (1.)

A30808-X3247-M41-3-7618

45


Information System

BTSold

MS

BTSnew

MSC

BSC

I (HO CMP) DATIN (HO CMP)

FACCH

Stop T8 SINTHINT (*) SININIRH (*) SOUINIRH (*) SINHOBSC (*) MRPCI DT1 (HOPER) Stop T_MSRFPCI RELRQ

(with HO cause)

SUCTCHSE (1.)

RELCN RCHRL (Old TCH) RCHRA MTCHBUTI (1.) (stop) AALTCHTI (1.) (stop)

Call continuation ...

(*)

Note: Subcounter depends on the handover cause value contained in the HANDOVER CONDITION INDICATION.

(**)

TTRAU is stopped when the BTS receives the (idle) TRAU frames from the TRAU. This happens when the BSC throughconnects the Asub-TCH to the Abis-TCH. In case of intra-BSC handover this is done after receipt of the HANDOVER DETECT message.

46

A30808-X3247-M41-3-7618

Information System


1.2.4.2

Unsuccessful Inter-Cell Handover Attempt, Intra-BSC, No TCH Available in Target Cell, FR Call

MS

BTSold

BTSnew

BSC

MSC


UI (MEAS REP) SACCH

UI (MEAS REP) BWHCI

SACCH

Start THORQST

Expiry THORQST

.. .. . .

(with HO cause)

.. .. . .

ATTCHSEI (1.)(**) ATCHSMBS (1.)(**) ATINHIRC (*)(**) NHOINRHA (3.)(**)

BWHCI (with HO cause)

ATTCHSEI (1.)(**) ATCHSMBS (1.)(**) ATINHIRC (*)(**) NHOINRHA (3.)(**)


(*) (**)

Note: Subcounter depends on the handover cause value contained in the HANDOVER CONDITON INDICATION. When the BSC receives an INTERCELL HANDOVER CONDITION INDICATION for a TCH with a valid target cell, it first checks the administrative state (locked/unlocked/shutting down) and the availability state (enabled/disabled) of the target BTS objects. Moreover, if the INTERCELL HANDOVER CONDITION INDICATION contains the cause "traffic", it checks the TCH load situation with respect to the threshold TRFLTH. Only if the BSC finds one target BTS in state "unlocked/enabled" and (in case of traffic handover) with a TCH load below the TRFLTH threshold, the BSC starts to search for an available TCH in the "idle list" of the target cell. Only in this case the measurements ATINHIRC (for the originating BTS) and ATTCHSEI (for the target BTS) are triggered. If no TCH can be found due to TCH congestion, "locked" state of the TRXs or/and "locked" state of the CHAN objects in the target BTS, ATCHSMBS is triggered for the target BTS in addition and the next target cell is analyzed. If no target BTS in state "unlocked/enabled" or (in case of traffic handover) no target cell with the TCH load below the threshold TRFLTH can be found, NHOINRHA is triggered. In this case neither ATINHIRC nor ATTCHSEI nor ATCHSMBS are increased.

A30808-X3247-M41-3-7618

47


1.2.4.3

Information System

Unsuccessful Inter-Cell Handover, Intra-BSC, with Reversion to Old TCH (T3124 Expiry), FR Call

BTSold

MS

BTSnew

BSC

MSC


UI (MEAS REP) SACCH

UI (MEAS REP) BWHCI

SACCH

Start THORQST

(with HO cause)

ATTCHSEI (1.) ATINHIRC (*) If last TCH start AALTCHTI (1.)

CHNAV (New TCH) Start TTRAU


Start T_MSRFPCI I (HO CMD)

DATRQ (HO CMD)

FACCH

Start T8

HO ACCESS FACCH

Start T3124 HO ACCESS FACCH

HO ACCESS does not get through***


HO ACCESS

FACCH

Expiry T3124

SABM ESTIN

FACCH

UA FACCH

I (HO FAIL) FACCH

DATIN (HO FAIL) (cause: protocol error, unspecified**)

Stop T8 HOFITABS UNINHOIE (*)

48

A30808-X3247-M41-3-7618

Information System

MS


BTSold

BTSnew

BSC

MSC

RCHRL (New TCH) RCHRA Reset TTRAU Reset T_MSRFPCI

MTCHBUTI (1.) (stop) AALTCHTI (1.) (stop)


(*)


(**)

The actual cause value used by the MS might differ from the one indicated in the message flow other cause values such as "abnormal release, timer expired" or "abnormal release, unspecified" etc. might be used. The handover might not only fail due to the fact that no PHYSICAL INFORMATION is received after transmission of the HANDOVER ACCESS on the target channel. The MS can still return to the old channel after it has received the PHYSICAL INFORMATION from the BTS. This happens when the layer 2 connection setup fails, i.e. when the MS does not receive any UA after repeated transmission of the SABM on the target channel.

(****)

A30808-X3247-M41-3-7618

49


1.2.4.4

Information System

Unsuccessful Inter-Cell Handover, Intra-BSC, with Loss of MS (Loss of HO CMD, T8
BTSold

MS

BTSnew

MSC

BSC


UI (MEAS REP) SACCH

UI (MEAS REP) BWHCI

SACCH

Start THORQST

(with HO cause)



CHNAK Start T_MSRFPCI DATRQ (HO CMD) I (HO CMD) Start T8

FACCH

HO CMD is lost ...

AININIRH (*) AOUINIRH (*) Expiry T8 UNIHIRLC DT1 (CL REQ) (cause: radio interface message failure)

NRCLRREQ (3.)

DT1 (CL CMD) NRCLRCMD (1.) RELRQ

DT1 (CL CMP)

RELCN RCHRL (Old TCH) RCHRA

50

A30808-X3247-M41-3-7618

Information System

MS


BTSold

BTSnew

MSC

BSC RLSD RLC

RCHRL (New TCH) RCHRA Reset TTRAU Reset T_MSRFPCI


Call release ...

(*)


A30808-X3247-M41-3-7618

51


1.2.4.5

Information System

Unsuccessful Inter-Cell Handover, Intra-BSC with Loss of MS (Loss of HO CMD, T8>TTRAU), FR Call (TTRAU Expiry)

BTSold

MS

BTSnew

MSC

BSC


UI (MEAS REP) SACCH

UI (MEAS REP) BWHCI

SACCH

Start THORQST

(with HO cause)




CHNAK Start T_MSRFPCI

I (HO CMD)

DATRQ (HO CMD) Start T8

FACCH

HO CMD is lost ...


Expiry TTRAU

CONFL

(Cause: remote transcoder failure)

NRFLTCH (8.) DT1 (CL REQ)

NRCLRREQ (3.)


DT1 (CL CMD) NRCLRCMD (1.) DT1 (CL CMP)

52

A30808-X3247-M41-3-7618

Information System

MS


BTSold

BTSnew

MSC

BSC RCHRL (New TCH)

RCHRA Reset T_MSRFPCI


RELRQ RLSD RELCN

RLC

RCHRL (Old TCH) RCHRA

(*)


A30808-X3247-M41-3-7618

53


1.2.4.6

Information System

Unsuccessful Inter-Cell Handover, Intra-BSC, with Loss of MS, Handover Access Failure (No SABM after Transmission of PHYSICAL INFO, [(NY1+1) * T3105]<
BTSold

MS

BTSnew

BSC

MSC


UI (MEAS REP) SACCH

UI (MEAS REP) SACCH

Start THORQST



MTCHBUTI (1.) start

CHNAK Start T_MSRFPCI DATRQ (HO CMD) I (HO CMD)

Start T8

FACCH

HO ACCESS FACCH

HANDO

Start T3124


Stop TTRAU (**) UI (PHYS INFO) FACCH

MS does not react to PHYS INFO, no SABM is received at the BTS.

Start T3105

UI (PHYS INFO)

Expiry T3105 FACCH


54

Start T3105

A30808-X3247-M41-3-7618

Information System

MS


BTSold

UI (PHYS INFO)

BTSnew

MSC

BSC

Expiry T3105 FACCH


Start T3105

Expiry T3105 (***) CONFL (cause: HO access failure)

NRFLTCH (6.) DT1 (CL REQ)

NRCLRREQ (3.)


DT1 (CL CMD) NRCLRCMD (1.) RCHRL (New TCH)

DT1 (CL CMP)

RCHRA MTCHBUTI (1.) (stop) AALTCHTI (1.) (stop) RELRQ

RLSD RLC

RELCN RCHRL (Old TCH) RCHRA

(*)


(***) Note: T3105 expires (NY1+1) times.

A30808-X3247-M41-3-7618

55


1.2.4.7

Information System

Successful Inter-Cell Handover (Intra-BSC) between Colocated Concentric Cells, FR Call

BTSold

MS

BTSnew

BSC

MSC


UI (MEAS REP) SACCH

UI (MEAS REP)

BWHCI

SACCH

(with HO cause)


PAREQ PAREA CHNAV (New TCH) Start TTRAU



Start T8

FACCH


HO ACCESS FACCH

HANDO

Start T3124

Stop TTRAU (**) UI (PHYS INFO) FACCH

Stop T3124

Start T3105 SABM

FACCH

Stop T3105 ESTIN

UA FACCH

56

TNTCHCL (1. for concentric cells)

A30808-X3247-M41-3-7618

Information System


BTSold

MS

BTSnew

MSC

BSC


FACCH

Stop T8 SINTHINT (*) SININIRH (*) SOUINIRH (*) SINHOBSC (*) MRPCI DT1 (HOPER) Stop T_MSRFPCI RELRQ

(with HO cause)

SUCTCHSE (1.)

RELCN RCHRL (Old TCH) RCHRA MTCHBUTI (1.) (stop) AALTCHTI (1.) (stop)


(*)


(**)


A30808-X3247-M41-3-7618

57


1.2.4.8

Information System

Successful Inter-Cell Handover, Intra-BTSE, Between Synchronized Cells, FR Call

BTSnew

BTSold

MS

BSC

MSC


UI (MEAS REP) SACCH

UI (MEAS REP)

BWHCI

SACCH

(with HO cause)

Start THORQST

ATTCHSEI (1.) ATINHIRC (*) If last TCH start AALTCHTI (1.) CHNAV (New TCH) (Activation type: related to synchronous handover)

Start TTRAU



(Synchronization Indicator: synchronized)

FACCH

HO ACCESS (***) FACCH

Start T8 AININIRH (*) AOUINIRH (*)

HO ACCESS (***)

FACCH

HO ACCESS (***) FACCH

HO ACCESS (***)

HANDO

FACCH

Stop TTRAU (**) SABM FACCH

ESTIN

UA FACCH

TNTCHCL (1.)

I (HO CMP) FACCH

DATIN (HO CMP) Stop T8 SINTHINT (*) SININIRH (*) SOUINIRH (*) SINHOBSC (*)

58

A30808-X3247-M41-3-7618

Information System

MS


BTSold

BTSnew

MSC

BSC MRPCI

Stop T_MSRFPCI RELRQ RELCN DT1 (HOPER) (with HO cause)

SUCTCHSE (1.) RCHRL (Old TCH) RCHRA MTCHBUTI (1.) (stop) AALTCHTI (1.) (stop)


(*)

Note: Subcounter depends on the handover cause value contained in the BWHCI.

(**)


(***)

HO ACCESS is transmitted exactly 4 times, the MS does not wait for any response from the BTS but directly sets up the layer 2 connection (using the SABM) after the last HO ACCESS.

A30808-X3247-M41-3-7618

59


1.2.4.9

Information System

Successful Inter-Cell Handover, Intra-BSC, MSC Controlled, FR Call

BTSold

MS

BTSnew

MSC

BSC

Call in progress...

UI (MEAS REP) SACCH

UI (MEAS REP) SACCH

UI (MEAS REP) BWHCI

SACCH

Start THORQST

DT1 (HO RQD)

(with HO cause)

Start T7 CR (HO REQ) ATTCHSEI (1.) if last TCH start AALTCHTI (1.) CHNAV (New TCH) Start TTRAU (**)


Start T_MSRFPCI Stop TTRAU (**)

CC (HO RAC; HO CMD) DT1 (HO CMD; HO CMD) (***) Stop T7

DATRQ (HO CMD) I (HO CMD)

AOUINIRH (*) AININIRH (*) Start T8

FACCH

HO ACCESS FACCH

HANDO

Start T3124

60

A30808-X3247-M41-3-7618

Information System


BTSold

MS

BTSnew

MSC

BSC

PHYS INFO FACCH

Stop T3124

Start T3105 SABM

FACCH

Stop T3105 ESTIN UA TNTCHCL (1.)

FACCH

I (HO CMP) FACCH

DATIN (HO CMP) DT1 (HO CMP) SUCTCHSE (1.) MRPCI Stop T_MSRFPCI

DT1 (CL CMD) (cause: handover successful)

SOUINIRH (*) SININIRH (*) NRCLRCMD (3.) Stop T8 RELRQ DT1 (CL CMP) RELCN RCHRL (Old TCH) RCHRA MTCHBUTI (stop) AALTCHTI (stop)

(*) (**)

Note: Subcounter depends on the handover cause value contained in the HANDOVER CONDITION INDICATION. TTRAU is stopped when the BTS receives the (idle) TRAU frames from the TRAU. This happens when the BSC throughconnects the Asub-TCH to the Abis-TCH. In case of MSC-controlled handover this is done on the CHANNEL ACTIVATION ACKNOWLEDGE for the TCH in the target BTS.

(***)

HANDOVER COMMAND contains the BCCH and BSIC frequency of an internal neighbour cell.

A30808-X3247-M41-3-7618

61


1.2.4.10

Information System

Successful SDCCH-SDCCH Inter-Cell Handover, Intra-BSC

BTSold

MS

BTSnew

BSC

MSC

SDCCH transaction or call in SDCCH phase in progress ... UI (MEAS REP) SACCH

UI (MEAS REP) SACCH

UI (MEAS REP)

BWHCI

SACCH

Start THORQST

(with HO cause)

NATTSDPE ATINHIRC (*) If last SDCCH start ASDCALTI CHNAV (New SDCCH) CHNAK Start T_MSRFPCI DATRQ (HO CMD)

I (HO CMD)

Start T8

SDCCH

AININIRH (*) AOUINIRH (*) AISHINTE

HO ACCESS SDCCH

Start T3124

HO ACCESS HANDO

SDCCH

UI (PHYS INFO) SDCCH

Stop T3124 SABM

Start T3105

SDCCH

Stop T3105 ESTIN

UA SDCCH

I (HO CMP) FACCH

DATIN (HO CMP) Stop T8 SINTHINT (*) SININIRH (*) SOUINIRH (*) SISHINTE SINHOBSC (*)

62

A30808-X3247-M41-3-7618

Information System

MS


BTSold

BTSnew

MSC

BSC MRPCI

DT1 (HOPER) Stop T_MSRFPCI

(with HO cause)

NASUSDPE RELRQ RELCN RCHRL (Old SDCCH) RCHRA ASDCALTI (stop)


(*)


A30808-X3247-M41-3-7618

63


1.2.4.11

Information System

Unsuccessful SDCCH-SDCCH Inter-Cell Handover Attempt, IntraBSC, No SDCCH Available in Target Cell

MS

BTSold

BTSnew

BSC

MSC

Call in progress...

UI (MEAS REP) SACCH

UI (MEAS REP) SACCH

UI (MEAS REP)

BWHCI

SACCH

Start THORQST

Expiry THORQST

.. .. . .

(with HO cause)

.. .. . .

NATTSDPE (**) ATSDCMBS (**) ATINHIRC (*)(**) NHOINRHA (3.)(**)


NATTSDPE (**) ATSDCMBS (**) ATINHIRC (*)(**) NHOINRHA (3.)(**)


(*) (**)

64

Note: Subcounter depends on the handover cause value contained in the HANDOVER CONDITON INDICATION. When the BSC receives an INTERCELL HANDOVER CONDITION INDICATION for and SDCCH-SDCCH handover with a valid target cell, it first checks the administrative state (locked/unlocked/shutting down) and the availability state (enabled/disabled) of the target BTS objects. Only if the BSC finds one target BTS in state "unlocked/enabled", the BSC starts to search for an available SDCCH in the "idle list" of the target cell. Only in this case the measurements ATINHIRC (for the originating BTS) and NATTSDPE (for the target BTS) are triggered. If no SDCCH can be found due to SDCCH congestion, "locked" state of the TRXs or/and "locked" state of the CHAN objects in the target BTS, ATSDCMBS is triggered for the target BTS in addition and the next target cell is analyzed. If no target BTS in state "unlocked/enabled" can be found, NHOINRHA is triggered. In this case neither ATINHIRC nor NATTSDPE nor ATSDCMBS are increased.

A30808-X3247-M41-3-7618

Information System


1.2.4.12

Unsuccessful SDCCH-SDCCH Inter-Cell Handover, Intra-BSC, with Loss of MS (Loss of HO CMD, T8 Expiry)

BTSold

MS

BTSnew

MSC

BSC


UI (MEAS REP) SACCH

UI (MEAS REP) BWHCI

SACCH

Start THORQST

(with HO cause)

NATTSDPE ATINHIRC (*) If last SDCCH start ASDCALTI

CHNAV (New SDCCH) CHNAK Start T_MSRFPCI I (HO CMD)


SDCCH

HO CMD is lost ...

AININIRH (*) AOUINIRH (*) AISHINTE

Expiry T8 UNIHIRLC UISHIRLC DT1 (CL REQ) NRCLRREQ (21.)


DT1 (CL CMD)

RELRQ

NRCLRCMD (13.) DT1 (CL CMP)

RELCN

RCHRL (Old SDCCH) RCHRA

A30808-X3247-M41-3-7618

65


MS

Information System

BTSold

BTSnew

MSC

BSC RLSD RLC

RCHRL (New SDCCH) RCHRA Reset T_MSRFPCI

ASDCALTI (stop)

Call release ...

(*)

66


A30808-X3247-M41-3-7618

Information System


1.2.5

Inter-Cell Handover, Inter-BSC

1.2.5.1

MS

Successful Inter-Cell Handover, Inter-BSC, FR Call

BTSold

BSCold

MSC

BSCnew

BTSnew


UI (MEAS REP) SACCH

UI (MEAS REP)

BWHCI

SACCH

(with HO cause)

Start THORQST

DT1 (HO RQD) CR (HO REQ)

Start T7

ATTCHSEI (1.) If last TCH start AALTCHTI (1.) CHNAV (New TCH) MTCHBUTI (1.) (start)

Start TTRAU

CHNAK CC (HO RAC; HO CMD) DT1 (HO CMD; HO CMD) Stop T7

Start Trr7 (***)


ATINBHDO (*) DATRQ (HO CMD) I (HO CMD) FACCH

Start T8 HO ACCESS

FACCH

Start T3124

HO ACCESS

FACCH

HANDO DT1 (HO DET) UI (PHYS INFO) Stop T3124

A30808-X3247-M41-3-7618

FACCH

Start T3105

67


MS

Information System

BTSold

BSCold

MSC

BSCnew

BTSnew

SABM FACCH

Stop T3105 ESTIN TNTCHCL (1.)

UA

FACCH

I (HO CMP) FACCH

DATIN (HO CMP) DT1 (HO CMP) Stop Trr7 (***)

SUCTCHSE (1.) MRPCI


Stop T8

Stop T_MSRFPCI

SUINBHDO (*) NRCLRCMD (3.) RELRQ RELCN

DT1 (CL CMP) RLSD

RCHRL (Old TCH) RCHRA MTCHBUTI (1.) (stop) AALTCHTI (1.) (stop) RLC


(*)


(**)

TTRAU is stopped when the BTS receives the (idle) TRAU frames from the TRAU. This happens when the BSC throughconnects the Asub-TCH to the Abis-TCH. In case of inter-BSC handover this is done on the CHANNEL ACTIVATION ACKNOWLEDGE for the TCH in the target BTS.

(***)

Trr7 is an MSC timer which supervises the receipt of a HO CMP after transmission of a HO CMD.

68

A30808-X3247-M41-3-7618

Information System


1.2.5.2

MS

Unsuccsessful Inter-Cell Handover, Inter-BSC, No TCH Available in Target Cell, FR Call

BTSold

BSCold

MSC

BSCnew

BTSnew


UI (MEAS REP) SACCH

UI (MEAS REP) SACCH


Start THORQST


Start T7

ATTCHSEI (1.)** ATCHSMBS (1.)** CREF (HO FAI) (cause: no radio resource available)

DT1 (HO RRJ)

NRINHDFL


Expiry T7 NHOINRHA (2.)*


(*)

(**)

Note: Subcounter (2.) of the measurement NHOINRHA is triggered when the administrable BSSMAP timer T7 (database parameter name BSCT7) expires; with suitable settings of BSCT7 this happens after the receipt of a HANDOVER REQUIRED REJECT message from the MSC. This means that the timer T7 must be set appropriately (e.g. BSCT7=HLFSEC-6) to ensure that NHOINRHA (2.) counts correctly in case of Inter-BSC handover. If - by chance - the call is released before T7 expires, NHOINRHA (2.) is not triggered. ATTCHSEI and ATCHSMBS are only triggered if the target BTS indicated in the HO REQ message is in state unlocked/enabled.

A30808-X3247-M41-3-7618

69


1.2.5.3

MS

Information System

Unsuccessful Inter-Cell Handover, Inter-BSC, with Reversion to Old TCH, FR Call (T3124 Expiry)

BTSold

BSCold

MSC

BSCnew

BTSnew


UI (MEAS REP) SACCH

UI (MEAS REP) SACCH


Start THORQST


Start T7


Start TTRAU


Start Trr7 (***)


ATINBHDO (*) I (HO CMD)

DATRQ (HO CMD)

FACCH

Start T8 HO ACCESS

FACCH

HO ACCESS does not get through*****

Start T3124

HO ACCESS

FACCH

Expiry T3124 SABM FACCH

70

ESTIN

A30808-X3247-M41-3-7618

Information System


MS

BTSold

BSCold

MSC

BSCnew

BTSnew

UA FACCH

I (HO FAIL) FACCH (cause: DATIN protocol error unspecified****)

(HO FAIL) Stop T8

DT1 (HO FAI) NRUNINHD

(cause: radio interface failure, reversion to old channel)

Stop Trr7 (***)

DT1 (CL CMD) (cause: equipment failure)

NRCLRCMD (4.) Reset T_MSRFPCI

RCHRL (New TCH) DT1 (CL CMP) RCHRA MTCHBUTI (1.) (stop) AALTCHTI (1.) (stop)

RLSD RLC

Call continuation ... (*)


(**)


(***)


The actual cause value used by the MS might differ from the one indicated in the message flow - other cause values such as "abnormal release, timer expired" or "abnormal release, unspecified" etc. might be used. (*****) The handover might not only fail due to the fact that no PHYSICAL INFORMATION is received after transmission of the HANDOVER ACCESS on the target channel. The MS can still return to the old channel after it has received the PHYSICAL INFORMATION from the BTS. This happens when the layer 2 connection setup fails, i.e. when the MS does not receive any UA after repeated transmission of the SABM on the target channel. (****)

A30808-X3247-M41-3-7618

71


1.2.5.4

MS

Information System

Unsuccessful Inter-Cell Handover, Inter-BSC with Loss of MS (Loss of HO CMD, T8
BTSold

BSCold

MSC

BSCnew

BTSnew


UI (MEAS REP) SACCH

UI (MEAS REP) BWHCI

SACCH

(with HO cause)

Start THORQST


Start T7


Start TTRAU CHNAK

CC (HO RAC; HO CMD) DT1 (HO CMD)


Stop T7

Start Trr7 (***)

ATINBHDO (*) I (HO CMD) FACCH

HO CMD is lost ...


Expiry T8 NRFLTCH (9.) DT1 (CL REQ) (cause: radio interface message failure)

NRCLRREQ (3.)

72

A30808-X3247-M41-3-7618

Information System

MS


BTSold

BSCold

MSC

BSCnew

BTSnew

DT1 (CL CMD) NRCLRCMD (1.) DT1 (CL CMP) DATRQ (CHREL) DESAC

RELIN

RLSD RLC


Expiry Trr7 (***)


DT1 (CL CMP)

RCHRL (New TCH) Reset T_MSRFPCI


RLSD RLC

(*)


(**)


(***)

Trr7 is an MSC timer which supervises the receipt of a HO CMP after transmission of a HO CMD. Its value is hardcoded to 15 sec..

A30808-X3247-M41-3-7618

73


1.2.5.5

MS

Information System

Unsuccessful Inter-Cell Handover, Inter-BSC with Loss of MS (Loss of HO CMD, T8>Trr7), FR Call (Trr7 Expiry)

BTSold

BSCold

MSC

BSCnew

BTSnew


UI (MEAS REP) SACCH

UI (MEAS REP) SACCH


Start THORQST


Start T7


Start TTRAU

CHNAK CC (HO RAC; HO CMD) Start T_MSRFPCI

DT1 (HO CMD)

Stop TTRAU (**)

Start Trr7 (***)

Stop T7 ATINBHDO (*) DATRQ (HO CMD) I (HO CMD) FACCH

Start T8

HO CMD is lost ... Expiry Trr7 DT1 (CL CMD) NRCLRCMD (2.)

DT1 (CL CMD)

(cause: call control) (cause: equipment failure)

NRCLRCMD (4.)

Reset T8 DT1 (CL CMP)

74

DT1 (CL CMP)

A30808-X3247-M41-3-7618

Information System

MS


BTSold

BSCold

MSC

BSCnew

BTSnew

RCHRL (New TCH) Reset T_MSRFPCI

RCHRA DATRQ (CHREL) MTCHBUTI (1.) (stop) AALTCHTI (1.) (stop)

DESAC RLSD

RLSD

RLC

RLC

RELIN


(*) (**)

Note: Subcounter depends on the handover cause value contained in the HANDOVER CONDITION INDICATION. TTRAU is stopped when the BTS receives the (idle) TRAU frames from the TRAU. This happens when the BSC throughconnects the Asub-TCH to the Abis-TCH. In case of inter-BSC handover this is done on the CHANNEL ACTIVATION ACKNOWLEDGE for the TCH in the target BTS.

(***)


A30808-X3247-M41-3-7618

75


1.2.5.6

MS

Information System

Unsuccessful Inter-Cell Handover, Inter-BSC, with Loss of MS, Handover Access Failure (No SABM received after Transmission) of PHYSICAL INFO, [(NY1+1) * T3105]<
BTSold

BSCold

MSC

BSCnew

BTSnew


UI (MEAS REP) SACCH

UI (MEAS REP) SACCH


Start THORQST


Start T7


Start TTRAU


Start Trr7 (***)


ATINBHDO (*) DATRQ (HO CMD) I (HO CMD) FACCH

Start T8 HO ACCESS

FACCH

Start T3124

HO ACCESS

FACCH

76

A30808-X3247-M41-3-7618

Information System

MS


BTSold

BSCold

MSC

BSCnew

BTSnew

HANDO DT1 (HO DET) UI (PHYS INFO) FACCH


Start T3105

Expiry T3105

UI (PHYS INFO)

FACCH


Start T3105

Expiry T3105

UI (PHYS INFO)

FACCH


Start T3105

Expiry T3105 (****) CONFL DT1 (CL REQ) (cause: radio interface message failure)

(cause: handover access failure)

NRCLRREQ (3.)

DT1 (CL CMD) NRCLRCMD (1.) DT1 (CL CMD)

A30808-X3247-M41-3-7618

77


MS

Information System

BTSold

BSCold

MSC

BSCnew

BTSnew

RCHRL RELIN RCHRA MTCHBUTI (1.) (Stop) AALTCHTI (1.) (Stop)

Expiry T8 NRFLTCH (9.) DT1 (CL REQ) (Cause: radio interface message failure)

NRCLRREQ (3.)

DT1 (CL CMD) NRCLRCMD (1.) DT1 (CL CMP) DATRQ (CHREL) DESAC

RLSD RLC

RCHRL (Old TCH) RELIN RCHRA

(*) (**)

Note: Subcounter depends on the handover cause value contained in the HANDOVER CONDITION INDICATION. TTRAU is stopped when the BTS receives the (idle) TRAU frames from the TRAU. This happens when the BSC throughconnects the Asub-TCH to the Abis-TCH. In case of inter-BSC handover this is done on the CHANNEL ACTIVATION ACKNOWLEDGE for the TCH in the target BTS.

(***)


(****)

When T3105 has expired NY1+1 times, the BTS sends the CONNECTION FAILURE INDICATION with cause “handover access failure”.

78

A30808-X3247-M41-3-7618

Information System


1.2.5.7

Successful Inter-Cell Handover, Inter-BSC, No TCH Available in First (external) Cell, Second Target Cell Belongs to Originating BSC, FR Call

i MS

The red colour indicates the BSC serving the first (really external) target cell in the target cell list of the HANDOVER REQUIRED message.

BTSold BTSnew (belongs to BSC A) (belongs to BSC A)

BSC A

MSC

BSC B


UI (MEAS REP) SACCH

UI (MEAS REP)

BWHCI

SACCH

Start THORQST

DT1 (HO RQD)

(with HO cause)

CR (HO REQ)

Start T7

ATTCHSEI (1.) ATCHSMBS (1.) CREF (HO FAI) CR (HO REQ)


ATTCHSEI (1.) if last TCH start AALTCHTI (1.)

NRINHDFL

CHNAV (New TCH) Start TTRAU (**)

MTCHBUTI (1.) (start) CHNAK CC (HO RAC; HO CMD)

Start T_MSRFPCI

DT1 (HO CMD; HO CMD) (***) Stop T7 AOUINIRH (*) AININIRH (*) DATRQ (HO CMD) I (HO CMD)

Start T8

FACCH

HO ACCESS FACCH

Start T3124

A30808-X3247-M41-3-7618

HANDO Stop TTRAU (**)

79


MS

Information System

BTSold BTSnew (belongs to BSC A) (belongs to BSC A)

BSC A

MSC

BSC B

PHYS INFO FACCH

Stop T3124

Start T3105 SABM

FACCH

Stop T3105 ESTIN UA TNTCHCL (1.)

FACCH

I (HO CMP) FACCH

DATIN (HO CMP) DT1 (HO CMP) SUCTCHSE (1.) MRPCI Stop T_MSRFPCI


SOUINIRH (*) SININIRH (*) NRCLRCMD (3.) Stop T8

RELRQ

DT1 (CL CMP) RELCN RCHRL (Old TCH) RCHRA MTCHBUTI (stop) AALTCHTI (stop)

(*) (**)

(***)

80

Note: Subcounter depends on the handover cause value contained in the HANDOVER CONDITION INDICATION. TTRAU is stopped when the BTS receives the (idle) TRAU frames from the TRAU. This happens when the BSC throughconnects the Asub-TCH to the Abis-TCH. In case of intra-BSC handover this is done after receipt of the HANDOVER DETECT message. HANDOVER COMMAND contains the BCCH and BSIC frequency of an internal neighbour cell.

A30808-X3247-M41-3-7618

Information System


1.2.5.8

MS

Successful SDCCH-SDCCH Inter-Cell Handover, Inter-BSC

BTSold

BSCold

MSC

BSCnew

BTSnew


UI (MEAS REP) SACCH

UI (MEAS REP)

BWHCI

SACCH

(with HO cause)

Start THORQST


Start T7

(channel type: SDCCH)

NATTSDPE If last SDCCH start ASDCALTI CHNAV (New SDCCH) CHNAK

CC (HO RAC; HO CMD) DT1 (HO CMD; HO CMD)

Start T_MSRFPCI

Start Trr7 (***)

Stop T7 ATINBHDO (*) AOINTESH

DATRQ (HO CMD) I (HO CMD) SDCCH

Start T8 HO ACCESS

SDCCH

Start T3124

HO ACCESS

SDCCH

HANDO DT1 (HO DET) UI (PHYS INFO) Stop T3124

A30808-X3247-M41-3-7618

SDCCH

Start T3105

81


MS

Information System

BTSold

BSCold

MSC

BSCnew

BTSnew

SABM SDCCH

Stop T3105 ESTIN UA SDCCH

I (HO CMP) SDCCH

DATIN (HO CMP) DT1 (HO CMP) Stop Trr7 (***)

NASUSDPE MRPCI

DT1 (CL CMD) Stop T8

(cause: handover successful)

Stop T_MSRFPCI

SUINBHDO (*) SOINTESH NRCLRCMD (3.) RELRQ RELCN

DT1 (CL CMP) RLSD

RCHRL (Old SDCCH) RCHRA ASDCALTI MBUSYSSP (n.) (**) (accumulation) RLC


(*)


(**)

Note: Subcounter of MBUSYSSP depends on type of original SCDDH transaction

(***)


82

A30808-X3247-M41-3-7618

Information System


1.2.5.9

MS

Unsuccsessful SDCCH-SDCCH Inter-Cell Handover, Inter-BSC, No SDCCH Available in Target Cell

BTSold

BSCold

MSC

BSCnew

BTSnew


UI (MEAS REP) SACCH

UI (MEAS REP) SACCH


Start THORQST


Start T7


NATTSDPE ATSDCMBS

CREF (HO FAI) (cause: no radio resource available)

DT1 (HO RRJ)

NRINHDFL

Expiry T7 NHOINRHA (2.)


Note: If the handover condition persists and another INTERCELL HANDOVER CONDITION INDICATION is received from the BTS after expiry of T7, the same procedure is repeated in exactly the same way.

A30808-X3247-M41-3-7618

83


1.2.5.10

MS

Information System

Unsuccessful SDCCH-SDCCH Inter-Cell Handover, Inter-BSC with Loss of MS (Loss of HO CMD, T8
BTSold

BSCold

MSC

BSCnew

BTSnew


UI (MEAS REP) SACCH

UI (MEAS REP) BWHCI

SACCH

(with HO cause)

Start THORQST


Start T7


NATTSDPE If last SDCCH start ASDCALTI CHNAV (New SDCCH) CHNAK

CC (HO RAC; HO CMD) DT1 (HO CMD)

Start T_MSRFPCI

Start Trr7 (***)

Stop T7 ATINBHDO (*) AOINTESH I (HO CMD) SDCCH


HO CMD is lost ...

Expiry T8 NRFLSDCC UMCSHLC DT1 (CL REQ) NRCLRREQ (21.)

84


A30808-X3247-M41-3-7618

Information System

MS


BTSold

BSCold

MSC

BSCnew

BTSnew

DT1 (CL CMD) DT1 (CL CMP) DATRQ (CHREL) DESAC

RELIN

RLSD RLC

RCHRL (Old SDCCH) RCHRA ASDCALTI MBUSYSSP (n.) (**) (accumulation) Expiry Trr7 (***)


NRCLRCMD (4.)

RCHRL (New SDCCH) Reset T_MSRFPCI

DT1 (CL CMP)

RCHRA ASDCALTI

RLSD RLC

(*)


(**)

Note: Subcounter of MBUSYSSP depends on type of original SCDDH transaction

(***)


A30808-X3247-M41-3-7618

85


1.2.6 1.2.6.1

Information System

Intra-Cell Handover Successful Intra-Cell Handover, FR Call Note: This message flow is valid for intra-cell handover due to quality, intra-cell handover complete <--> inner in concentric cells and intra-cell handover far <--> near in extended cells. The difference just consists in the handover cause.

i

MS

BTS

BSC

MSC


UI (MEAS REP) SACCH

UI (MEAS REP) WIHCI

SACCH

(with HO cause)

Start THORQST

ATTCHSEI (1.) If last TCH start AALTCHTI (1.) CHNAV (New TCH) Start TTRAU


CHNAK Start T_MSRFPCI DATRQ (ASS CMD)

I (ASS CMD)

Start T10

Old FACCH

SABM ESTIN

New FACCH

Stop TTRAU (**)

ATINHIAC (*) TNTCHCL (1.)

UA New FACCH

I (ASS CMP) New FACCH

DATIN (ASS CMP) Stop T10 SINTHITA (*) SINHOBSC (*)

86

A30808-X3247-M41-3-7618

Information System

MS


BTS

BSC

MSC DT1 (HOPER)

SUCTCHSE (1.)

(with HO cause)

MRPCI Stop T_MSRFPCI RELRQ RELCN RCHRL (Old TCH) RCHRA MTCHBUTI (1.) (stop) AALTCHTI (1.) (stop)


(*) (**)

Note: Subcounter depends on the handover cause value contained in the HANDOVER CONDITION INDICATION. TTRAU is stopped when the BTS receives the (idle) TRAU frames from the TRAU. This happens when the BSC throughconnects the Asub-TCH to the Abis-TCH. In case of intra-cell handover this is done after receipt of the ESTABLISH INDICATION for the target TCH.

A30808-X3247-M41-3-7618

87


1.2.6.2

Information System

Unsuccessful Intra-Cell Handover Due to Quality, No TCH Available, FR Call

MS

BTSold

BTSnew

BSC

MSC


UI (MEAS REP) SACCH

UI (MEAS REP) WIHCI

SACCH

Start THORQST

Expiry THORQST

(cause: downlink/uplink quality)

ATTCHSEI (1.) ATCHSMBS (1.) NHOINRHA (4.)

BWHCI (**) (cause: downlink/uplink quality)

ATTCHSEI (1.)(BTS new) ATINHIRC (*) If last TCH start AALTCHTI (1.)

Call continuation with inter-cell handover attempt...

(*) (**)

88

Note: Subcounter depends on the handover cause value contained in the HANDOVER CONDITION INDICATION. Only for intra-cell handover due to quality. An inter-cell handover due to quality is triggered, if the handover conditions persist and the call is still on the old TCH when the next HANDOVER CONDITION INDICATION is sent after expiry of THORQST.

A30808-X3247-M41-3-7618

Information System


1.2.6.3

Unsuccessful Intra-Cell Handover Due to Quality with Reversion to Old TCH, FR Call

MS

BTS

BSC

MSC


UI (MEAS REP) SACCH

UI (MEAS REP) WIHCI

SACCH

Start THORQST


ATTCHSEI (1.) If last TCH start AALTCHTI (1.)




I (ASS CMD)

Start T10

Old FACCH

SABM

ATINHIAC (*)

New FACCH

Access to target channel fails ... SABM

ESTIN

Old FACCH

UA I (ASS FAIL) Old FACCH

(cause: protocol error unspecified)

DATIN (ASS FAIL) Stop T10 UNINHOIA (*) RCHRL (New TCH) Reset TTRAU

Reset T_MSRFPCI

A30808-X3247-M41-3-7618

89


Information System

MS

BTS

BSC

MSC

RCHRA MTCHBUTI (1.)(stop) AALTCHTI (1.)(stop)

UI (MEAS REP) SACCH

UI (MEAS REP) SACCH

Expiry THORQST BWHCI (**) (cause:downlink/uplink quality)

Call continuation with inter-cell handover attempt ...

(*) (**)

90

Note: Subcounter depends on the handover cause value contained in the HANDOVER CONDITION INDICATION. Only for intra-cell handover due to quality. An inter-cell handover due to quality is triggered, if the handover conditions persist and the call is still on the old TCH when the next HANDOVER CONDITION INDICATION is sent after expiry of THORQST.

A30808-X3247-M41-3-7618

Information System


1.2.6.4

Unsuccessful Intra-Cell Handover with Loss of MS (Loss of ASS CMD, T10 < TTRAU), FR Call (T10 Expiry)

MS

BTS

BSC

MSC


UI (MEAS REP)

WIHCI

SACCH

(with HO cause)

Start THORQST

CHNAV (New TCH)



Start TTRAU CHNAK Start T_MSRFPCI

DATRQ (ASS CMD)

I (ASS CMD)

Start T10

Old FACCH

ASS CMD is lost ...

ATINHIAC (*)

Expiry T10 UNIHIALC DT1 (CL REQ) NRCLRREQ (3.)

(cause, radio interface message failure)

DT1 (CL CMD) NRCLRCMD (1.) DT1 (CL CMP) RELRQ

RLSD RLC

RELCN RCHRL (New TCH) Reset TTRAU Reset T_MSRFPCI RCHRA MTCHBUTI (1.) (stop) AALTCHTI (1.) (stop)

A30808-X3247-M41-3-7618

91


MS

Information System

BTS

BSC

MSC

RCHRL (Old TCH) RCHRA MTCHBUTI (1.) (stop)

(*)

92


A30808-X3247-M41-3-7618

Information System


1.2.6.5

Unsuccessful Intra-Cell Handover with Loss of MS (Loss of ASS CMD, T10>TTRAU), FR Call (TTRAU Expiry)

MS

BTS

BSC

MSC


UI (MEAS REP)

WIHCI

SACCH

(with HO cause)

Start THORQST




Start T_MSRFPCI I (ASS CMD)

DATRQ (ASS CMD) Start T10

Old FACCH

ASS CMD is lost ...

ATINHIAC (*)

Expiry TTRAU

CONFL (cause: remote transcoder failure)

NRFLTCH DT1 (CL REQ) (cause, radio interface message failure)

NRCLRREQ (3.)


RELRQ RELCN RCHRL (New TCH) Reset T_MSRFPCI RCHRA

MTCHBUTI (1.) (stop)

A30808-X3247-M41-3-7618

93


MS

Information System

BTS

BSC

MSC RLSD

RCHRL (Old TCH) RLC RCHRA MTCHBUTI (1.) (stop)

(*)

94


A30808-X3247-M41-3-7618

Information System


1.2.6.6

Successful Intra-Cell Handover Due to Quality, MSC Controlled, FR Call

MS

BTS

BSC

MSC


UI (MEAS REP) SACCH

UI (MEAS REP) WIHCI

SACCH

DT1 (HO RQD)


Start T7 CR (HO REQ) ATTCHSEI (1.) If last TCH start AALTCHTI (1.)



Start T_MSRFPCI

CC (HO RAC; HO CMD)

Stop TTRAU (**)

DT1 (HO CMD; HO CMD) Stop T7

DATRQ (HO CMD)

I (HO CMD)

Start T8

Old FACCH

HO ACCESS New FACCH

Start T3124 HO ACCESS HANDO

New FACCH

DT1 (HO DET)

UI (PHYS INFO) New FACCH

Stop T3124

Start T3105 SABM

New FACCH

Stop T3105 ESTIN

UA New FACCH

A30808-X3247-M41-3-7618

TNTCHCL (1.)

95


Information System

MS

BTS

BSC

MSC


New FACCH

DT1 (HO CMP) MRPCI Stop T_MSRFPCI

DT1 (CL CMD) Stop T8


NRCLRCMD (3.) DT1 (CL CMP) RELRQ RELCN

RLSD

RCHRL (Old TCH)

RLC



(**)

96

TTRAU is stopped when the BTS receives the (idle) TRAU frames from the TRAU. This happens when the BSC throughconnects the Asub-TCH to the Abis-TCH. In case of MSC controlled handover this is done on the CHANNEL ACTIVATION ACKNOWLEDGE for the TCH in the target BTS.

A30808-X3247-M41-3-7618

Information System


1.2.6.7

Successful SDCCH-SDCCH Intra-Cell Handover

MS

BTS

BSC

MSC


UI (MEAS REP) SACCH

UI (MEAS REP) WIHCI

SACCH

(with HO cause)

Start THORQST

NATTSDPE ASDCALTI (start) CHNAV (New SDCCH) CHNAK Start T_MSRFPCI DATRQ (ASS CMD)

I (ASS CMD)

Start T10

Old SDCCH

SABM

ATINHIAC (*) AISHINTR ESTIN

New SDCCH

UA New SDCCH

I (ASS CMP) New SDCCH

DATIN (ASS CMP) Stop T10 SINTHITA (*) SISHINTR SINHOBSC (*) DT1 (HOPER) NASUSDPE

(with HO cause)


A30808-X3247-M41-3-7618

97


MS

Information System

BTS

BSC

MSC

RELRQ RELCN RCHRL (Old SDCCH) RCHRA ASDCALTI (stop) MBUSYSSP (n.) (accumulation)


(*)

98


A30808-X3247-M41-3-7618

Information System


1.2.7

Directed Retry, Intra-BSC

1.2.7.1

Successful Directed Retry, Intra-BSC, FR Call

BTSnew

BTSold

MS

MSC

BSC


UI (MEAS REP) SACCH

ATTCHSEI (1.) (*) ATCHSMBS (1.) (*) TASSATT (2.)

UI (MEAS REP) FHREQ

SACCH

UI (MEAS REP) SACCH

BWHCI (cause: ’forced’, target cell list)

ATINHIRC (7.) ATTCHSEI (1.) If last TCH start AALTCHTI (1.) (**)

CHNAV (New TCH) Start TTRAU Start TIMERFHO

(contains CGI of BTS0 and GSM08.08 cause ’forced’)

MTCHBUTI (1.)

CHNAK Start T_MSRFPCI DATRQ (HO CMD)

I (HO CMD)

Start T8

SDCCH

HO ACCESS

AOUINIRH (7.) AININIRH (7.)

FACCH


(HANDO) Stop TTRAU (***) UI (PHYS INFO) FACCH

Stop T3124

Start T3105 SABM FACCH

Stop T3105 ESTIN UA FACCH

A30808-X3247-M41-3-7618

TNTCHCL (1.)

99


MS

Information System

BTSold

BTSnew

I (HO CMP)

BSC

MSC

DATIN (HO CMP)

FACCH

Stop T8 SOUINIRH (7.) SININIRH (7.) SINHOBSC (7.) SINTHINT (7.) DT1 (ASS COM) SUCTCHSE (1.) TASSSUCC (4.) MRPCI Stop T_MSRFPCI RELRQ RELCN RCHRL (SDCCH) RCHRA ASDCALTI (stop) MBUSYSSP (1.) (accumulation) DATRQ (CHMM)

I (CHMM) FACCH

I (CHMMACK)

DATIN (CHMMACK)

FACCH

DT1 (ALERT) DATRQ (ALERT) DT1 (CONNECT)

I (ALERT) FACCH

DATRQ (CONNECT)

I (CONNECT) FACCH

I (CONACK) FACCH

DATIN (CONACK) DT1 (CONACK)

Call continuation ... (*) (**) (***)

100

Event is counted for the serving cell. Event is counted for the target cell. TTRAU is stopped when the BTS receives the (idle) TRAU frames from the TRAU. This happens when the BSC throughconnects the Asub-TCH to the Abis-TCH. In case of intra-BSC directed retry this is done on receipt of the HANDOVER DETECT message.

A30808-X3247-M41-3-7618

Information System


1.2.7.2

Unsuccessful Directed Retry, Intra-BSC, No Target Cell Available, FR Call

MS

BTS

BSC

MSC

Call setup ... DT1 (ASS REQ) UI (MEAS REP) ATTCHSEI (1.) ATCHSMBS (1.) TASSATT (2.)

SACCH

UI (MEAS REP) SACCH

FHREQ UI (MEAS REP) BWHCI

SACCH

(cause: ’forced’,empty target cell list)

NHOINRHA (1.) DT1 (ASS FAI) TASSFAIL (8.)


DATRQ (DISC) DT1 (DISC) I (DISC) SDCCH

Call release ...

A30808-X3247-M41-3-7618

101


1.2.7.3

Information System

Unsuccessful Directed Retry, Intra-BSC, 1 Target Cell Available, Target Cell Congested, FR Call

BTSnew

BTSold

MS

MSC

BSC

Call setup ... DT1 (ASS REQ) UI (MEAS REP)

ATTCHSEI (1.) (*) ATCHSMBS (1.) (*) TASSATT (2.)

SACCH

UI (MEAS REP) FHREQ

SACCH

UI (MEAS REP)

BWHCI

SACCH

(cause: ’forced’, one target cell included)

ATINHIRC (7.) ATTCHSEI (1.) (**) ATCHSMBS (1.) (**) DT1 (ASS FAI)

TASSFAIL (8.)


DT1 (DISC) DATRQ (DISC) I (DISC)

(cause: normal, unspecified)

SDCCH

Call release ...

(*) (**)

102

Event is counted for the serving cell. Event is counted for the target cell.

A30808-X3247-M41-3-7618

Information System


1.2.7.4

Unsuccessful Directed Retry, Intra-BSC, with Reversion to SDCCH, FR Call (T3124 Expiry)

BTSold

MS

BTSnew

MSC

BSC

Call setup ... DT1 (ASS REQ) ATTCHSEI (1.) (*) ATCHSMBS (1.) (*) TASSATT (2.)

UI (MEAS REP) SACCH

FHREQ

UI (MEAS REP) BWHCI

SACCH

UI (MEAS REP)

(cause: ’forced’, target cell list)

ATINHIRC (7.) ATTCHSEI (1.) (**) If last TCH start AALTCHTI (1.) (**)

SACCH

CHNAV (New TCH) Start TIMERFHO Start TTRAU



CHNAK Start T_MSRFPCI DATRQ (HO CMD)

I (HO CMD)

Start T8

SDCCH


HO ACCESS FACCH HO ACCESS does not get through****


Expiry T3124

SABM

SDCCH

ESTIN

UA SDCCH

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103


Information System

BTSnew

BTSold

MS

MSC

BSC

I (HO FAIL) DATIN (HO FAIL)

SDCCH

(cause: protocol error, unspecified***)

Stop T8 HOFITABS UNINHOIE (7.) DT1 (ASS FAI) (cause: radio interface failure - reversion to old channel)

TASSFAIL (7.) RCHRL (New TCH) Reset TTRAU Reset T_MSRFPCI RCHRA MTCHBUTI (1.) (stop) AALTCHTI (1.) (stop) DATRQ (DISC)

I (DISC) SDCCH

DT1 (DISC) (cause: normal, unspecified)

Call release ...

(*) (**)


The actual cause value used by the MS might differ from the one indicated in the message flow - other cause values such as "abnormal release, timer expired" or "abnormal release, unspecified" etc. might be used. (*****) The handover might not only fail due to the fact that no PHYSICAL INFORMATION is received after transmission of the HANDOVER ACCESS on the target channel. Possible problem scenarios are: - HO ACCESS not correctly received at BTS - PHYS INFO not correctly received at MS The MS can still return to the old channel after it has received the PHYSICAL INFORMATION from the BTS. This happens when the layer 2 connection setup fails, i.e. when the MS does not receive any UA after repeated transmission of the SABM on the target channel. (****)

104

A30808-X3247-M41-3-7618

Information System


1.2.7.5

Unsuccessful Directed Retry, Intra-BSC, with Loss of MS (Loss of HO CMD, T8 < TTRAU), FR Call (T8 Expiry)

BTSold

MS

BTSnew

MSC

BSC


UI (MEAS REP) SACCH

FHREQ

UI (MEAS REP) BWHCI

SACCH

UI (MEAS REP)

(cause: ’forced’, target cell list)


SACCH




CHNAK

Start T_MSRFPCI DATRQ (HO CMD) I (HO CMD) SDCCH

HO CMD is lost ...

Start T8 AOUINIRH (7.) AININIRH (7.)

Expiry T8 UNIHIRLC

DT1 (CL REQ) NRCLRREQ (3.)


DT1 (CL CMD) NRCLRCMD (1.)

A30808-X3247-M41-3-7618

105


MS

Information System

BTSold

BTSnew

MSC

BSC DT1 (CLCMP)

RCHRL (New TCH) Reset TTRAU Reset T_MSRFPCI Reset TIMERFHO RCHRA MTCHBUTI (1.) (stop) AALTCHTI (1.) (stop) RLSD RLC RELRQ RELCN RCHRL (SDCCH) RCHRA ASDCALTI (stop) MBUSYSSP (1.) (accumulation)

(*) (**)

106


A30808-X3247-M41-3-7618

Information System


1.2.7.6

Unsuccessful Directed Retry, Intra-BSC, with Loss of MS (Loss of HO CMD, T8 > TTRAU), FR Call (TTRAU Expiry)

BTSold

MS

BTSnew

MSC

BSC


UI (MEAS REP) SACCH

FHREQ

UI (MEAS REP) SACCH

BWHCI

UI (MEAS REP)

(cause: ’forced’)


SACCH




CHNAK

Start T_MSRFPCI I (HO CMD)


SDCCH

HO CMD is lost ...


Expiry TTRAU

CONFL

(cause: remote transcoder failure)

NRFLTCH (8.) DT1 (CL REQ) (cause: radio interface message failure)

NRCLRREQ (3.)

DT1 (CL CMD) NRCLRCMD (1.) DT1 (CLCMP)

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107


MS

Information System

BTSold

BTSnew

MSC

BSC

RCHRL (New TCH) Reset T_MSRFPCI RCHRA MTCHBUTI (1.) (stop) AALTCHTI (1.) (stop) RELRQ RELCN RCHRL (SDCCH) RCHRA ASDCALTI (stop) MBUSYSSP (1.) (accumulation) RLSD RLC

(*) (**)

108


A30808-X3247-M41-3-7618

Information System


1.2.8

Directed Retry, Inter-BSC

1.2.8.1

MS

Successful Directed Retry, Inter-BSC, FR Call

BTSold

BSCold

MSC

BSCnew

BTSnew

Call setup ... DT1 (ASS REQ) ATTCHSEI (1.) ATCHSMBS (1.) TASSATT (2.) UI (MEAS REP) SACCH

FHREQ

UI (MEAS REP) BWHCI

SACCH

UI (MEAS REP)

DT1 (ASS FAI)


SACCH

(cause: directed retry)

TASSFAIL (9.) DT1 (HO RQD) (cause: directed retry)

CR (HO REQ) (cause: directed retry)

Start T7


Start TTRAU Start TIMERFHO

CHNAK Start T_MSRFPCI CC (HO RAC; HO CMD)

Stop TTRAU (**)


Start Trr7 (***)

ATINBHDO (7.) I (HO CMD)

DATRQ (HO CMD)

SDCCH

A30808-X3247-M41-3-7618

Start T8

109


MS

BTSold

Information System

BSCold

MSC

BSCnew

BTSnew

HO ACCESS FACCH

Start T3124

HANDO

DT1 (HO DET) UI (PHYS INFO)

FACCH

Stop T3124

Start T3105 SABM

FACCH

Stop T3105 ESTIN TNTCHCL (1.) UA FACCH

I (HO CMP) FACCH

DATIN (HO CMP) DT1 (HO CMP) DT1 (CL CMD) Stop T8


SUCTCHSE (1.) MRPCI Stop T_MSRFPCI

SUINBHDO (7.)

Release of resources... DATRQ (CHMM) I (CHMM) FACCH

I (CHMMACK) FACCH

DATIN (CHMMACK)

DT1 (ALERT)

DATRQ (ALERT)

I (ALERT) FACCH

DT1 (CONNECT) DATRQ (CONNECT) I (CONNECT) FACCH

110

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Information System

MS


BTSold

BSCold

MSC

BSCnew

BTSnew

I (CONACK) FACCH

DT1 (CONACK)

DATIN (CONACK)


(**)

(***)

TTRAU is stopped when the BTS receives the (idle) TRAU frames from the TRAU. This happens when the BSC throughconnects the Asub-TCH to the Abis-TCH. In case of inter-BSC directed retry this is done on the CHANNEL ACTIVATION ACKNOWLEDGE for the TCH in the target BTS. Trr7 is an MSC timer which supervises the receipt of a HO CMP after transmission of a HO CMD.

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111


1.2.8.2

MS

Information System

Unsuccessful Directed Retry, Inter-BSC, FR Call, no Radio Resource available in Target Cell

BTSold

BSCold

MSC

BSCnew

BTSnew


FHREQ

UI (MEAS REP) SACCH

UI (MEAS REP) SACCH

BWHCI DT1 (ASS FAI)





Start T7

ATTCHSEI (1.) If last TCH start AALTCHTI (1.) CREF (HO FAI) (cause: no radio resource available)

DT1 (HO RRJ) (cause: no radio resource available)

NRINHDFL

Expiry T7* NHOINRHA (2.)* DT1 (CLCMD) (cause: call control)

Call release ...

(*)

112

Note: NHOINRHA (2.) might not count in case of Inter-BSC directed retry due to the following reasons: If the MSC has rejected the inter-BSC directed retry handover attempt by sending a HANDOVER REQUIRED REJECT, it will immediately release the resources by sending a CLEAR COMMAND to the BSC. If the CLEAR COMMAND arrives before T7 expires, NHOINRHA (2.) is not triggered. This will happen with normal settings of BSCT7 (e.g. BSCT7=HLFSEC-6).

A30808-X3247-M41-3-7618

Information System


1.2.8.3

MS

Unsuccessful Directed Retry, Inter-BSC, with Reversion to SDCCH, FR Call (T3124 Expiry)

BTSold

BSCold

MSC

BSCnew

BTSnew

Call setup ... DT1 (ASS REQ) ATTCHSEI (1.) ATCHSMBS (1.) TASSATT (2.)

UI (MEAS REP) SACCH

UI (MEAS REP) SACCH

FHREQ

UI (MEAS REP) SACCH

BWHCI

DT1 (ASS FAI)





Start T7 ATTCHSEI (1.) If last TCH start AALTCHTI (1.) CHNAV (New TCH) MTCHBUTI (1.) (start)

Start TTRAU

Start TIMERFHO CHNAK CC (HO RAC; HO CMD)

Start T_MSRFPCI


Start Trr7 (***)

ATINBHDO (7.) I (HO CMD)

DATRQ (HO CMD)

SDCCH

A30808-X3247-M41-3-7618

Start T8

113


MS

Information System

BTSold

BSCold

MSC

BSCnew

BTSnew

HO ACCESS FACCH

HO ACCESS does not get through****

HO ACCESS FACCH

Expiry T3124 SABM SDCCH

ESTIN

UA SDCCH

I (HO FAIL) SDCCH

DATIN (HO FAIL) (cause: abnormal release, timer expired****)

Stop T8 NRUNINHD DT1 (HO FAIL) (cause: radio interface failure, reversion to old channel)


NRCLRCMD (4.)

DT1 (CL CMP) RCHRL (New TCH) Reset TIMERFHO Reset T_MSRFPCI RCHRA MTCHBUTI (1.) (stop) AALTCHTI (1.) (stop) RLSD RLC CL CMD (cause: call control)

Call release ...

114

A30808-X3247-M41-3-7618

Information System

(***) (****)


Trr7 is an MSC timer which supervises the receipt of a HO CMP after transmission of a HO CMD. The actual cause value used by the MS might differ from the one indicated in the message flow - other cause values such as "abnormal release, timer expired" or "abnormal release, unspecified" etc. might be used.

(*****) The handover might not only fail due to the fact that no PHYSICAL INFORMATION is received after transmission of the HANDOVER ACCESS on the target channel. The MS can still return to the old channel after it has received the PHYSICAL INFORMATION from the BTS. This happens when the layer 2 connection setup fails, i.e. when the MS does not receive any UA after repeated transmission of the SABM on the target channel.

A30808-X3247-M41-3-7618

115


1.2.8.4

MS

Information System

Unsuccessful Derected Entry, Inter-BSC, with Loss of MS (Loss of HO CMD, T8 < Trr7), FR Call (T8 Expiry)

BTSold

BSCold

MSC

BSCnew

BTSnew


UI (MEAS REP) SACCH


UI (MEAS REP) SACCH

FHREQ

UI (MEAS REP) SACCH

BWHCI

DT1 (ASS FAI)




Start T7



Start TTRAU

Start TIMERFHO CHNAK Start T_MSRFPCI CC (HO RAC; HO CMD) DT1 (HO CMD; HO CMD) Stop T7

Stop TTRAU (**)

Start Trr7 (***)

ATINBHDO (7.) DATRQ (HO CMD) I (HO CMD) SDCCH

Start T8

HO CMD is lost ...

116

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Information System

MS


BTSold

BSCold

MSC

BSCnew

BTSnew

Expiry T8 NRSLSDCC DT1 (CLREQ) (cause: radio interface msg. failure)

DATRQ (CHREL) (cause: abnormal release, unspecified)

DT1 (CL CMD) DT1 (CL CMP)

DESAC RELIN RCHRL (New TCH)

RLSD RLC

RCHRA MTCHBUTI (1.) (stop) AALTCHTI (1.) (stop) Expiry Trr7 DT1 (CL CMD) (cause: equipment failure)

NRCLRCMD (4.) RCHRL Reset TIMERFHO Reset T_MSRFPCI RCHRA


DT1 (CL CMP) RLSD RLC

(***)


A30808-X3247-M41-3-7618

117


1.2.8.5

MS

Information System

Unsuccessful Directed Retry, Inter-BSC, with Loss of MS (Loss of HO CMD, T8 > Trr7), FR Call (Trr7 Expiry)

BTSold

BSCold

MSC

BSCnew

BTSnew


FHREQ

UI (MEAS REP) SACCH

UI (MEAS REP) SACCH

BWHCI DT1 (ASS FAI)




Start T7



Start TTRAU

Start TIMERFHO CHNAK Start T_MSRFPCI Stop TTRAU (**)

118

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Information System


MS

BTSold

BSCold

MSC

BSCnew

BTSnew

CC (HO RAC; HO CMD)

DT1 (HO CMD; HO CMD) Start Trr7 (***)

Stop T7 ATINBHDO (7.) I (HO CMD)

DATRQ (HO CMD)

SDCCH

Start T8

HO CMD is lost ...

Expiry Trr7 DT1 (CL CMD) NCLRCMD (2.)

(cause: call control)


NCLRCMD (4.) RCHRL (New TCH)

Reset T8

Reset TIMERFHO

RELRQ

Reset T_MSRFPCI DT1 (CL CMP) RCHRA

RELCN RLSD RCHRL (SDCCH) RCHRA

DT1 (CL CMP)

MTCHBUTI (1.) (stop) AALTCHTI (1.) (stop) RLC

(***)


RLSD RLC


A30808-X3247-M41-3-7618

119


1.2.9

Information System

Forced Handover Due to O & M

1.2.9.1

Successful Forced Handover Due to O & M

BTSnew

BTSold

MS

BSC

MSC

Call in progress, operator initiated shutdown of a BTS, TRX or TCH... UI (MEAS REP) SACCH

UI (MEAS REP) FHREQ

SACCH

UI (MEAS REP) SACCH

BWHCI (cause: ’forced’, target cell list)

ATINHIRC (8.) ATTCHSEI (1.) If last TCH start AALTCHTI (1.) (**)



MTCHBUTI (1.)

CHNAK Start T_MSRFPCI DATRQ (HO CMD) I (HO CMD) Start T8

SDCCH

HO ACCESS


FACCH


(HANDO) Stop TTRAU (***) UI (PHYS INFO) FACCH

Stop T3124

Start T3105 SABM FACCH

Stop T3105 ESTIN UA FACCH

120

TNTCHCL (1.)

A30808-X3247-M41-3-7618

Information System

MS


BTSold I (HO CMP)

FACCH

BTSnew

BSC

MSC

DATIN (HO CMP) Stop T8 SOUINIRH (8.) SININIRH (8.) SINHOBSC (16.) SINTHINT (8.) DT1 (HO PER) MRPCI

(cause: O & M intervention)


(*) (**) (***)

Event is counted for the serving cell. Event is counted for the target cell. TTRAU is stopped when the BTS receives the (idle) TRAU frames from the TRAU. This happens when the BSC throughconnects the Asub-TCH to the Abis-TCH. In case of intra-BSC directed retry this is done on receipt of the HANDOVER DETECT message.

A30808-X3247-M41-3-7618

121


1.2.9.2

MS

Information System

Successful Forced Handover Due to O & M, Inter-BSC, FR Call

BTSold

BSCold

MSC

BSCnew

BTSnew

Call in progress, operator initiated shutdown of a BTS, TRX or TCH... UI (MEAS REP) SACCH

FHREQ

UI (MEAS REP) BWHCI

SACCH

UI (MEAS REP)


DT1 (HO RQD)

SACCH


Start T7

CR (HO REQ) (cause: O & M intervention)

ATTCHSEI (1.) If last TCH start AALTCHTI (1.) CHNAV (New TCH)


Start TTRAU Start TIMERFHO

CHNAK Start T_MSRFPCI CC (HO RAC; HO CMD)

Stop TTRAU (**)

DT1 (HO CMD; HO CMD) Start Trr7 (***)

Stop T7 ATINBHDO (8.) I (HO CMD) SDCCH

DATRQ (HO CMD) Start T8 HO ACCESS

FACCH

Start T3124

DT1 (HO DET)

HANDO

UI (PHYS INFO) FACCH

Stop T3124

Start T3105 SABM

FACCH

Stop T3105

122

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Information System

MS


BTSold

BSCold

MSC

BSCnew

BTSnew ESTIN

TNTCHCL (1.) UA FACCH

I (HO CMP) FACCH

DATIN (HO CMP) DT1 (HO CMP) DT1 (CL CMD) (cause: handover successful)

Stop T8

SUCTCHSE (1.) MRPCI Stop T_MSRFPCI

SUINBHDO (8.)

Release of resources in originating cell and call continuation in target cell ...

(**)

TTRAU is stopped when the BTS receives the (idle) TRAU frames from the TRAU. This happens when the BSC throughconnects the Asub-TCH to the Abis-TCH. In case of inter-BSC directed retry this is done on the CHANNEL ACTIVATION ACKNOWLEDGE for the TCH in the target BTS.

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123


1.2.9.3

Information System

Successful Forced Intra-Cell Handover Due to O & M, FR Call

MS

BTS

BSC

MSC

Call in progress, operator initiated shutdown of a TRX or TCH... CHNAV (New TCH) Start TTRAU



I (ASS CMD)

Start T10

Old FACCH

SABM

ATINHIAC (7.)

ESTIN

New FACCH

Stop TTRAU (**)

TNTCHCL (1.)

UA New FACCH


DATIN (ASS CMP) Stop T10 SINTHITA (7.) SINHOBSC (16.) DT1 (HOPER) SUCTCHSE (1.)


MRPCI Stop T_MSRFPCI RELRQ RELCN RCHRL (Old TCH) RCHRA MTCHBUTI (1.) (stop) AALTCHTI (1.) (stop)

Call continuation ... (**)

124

TTRAU is stopped when the BTS receives the (idle) TRAU frames from the TRAU. This happens when the BSC throughconnects the Asub-TCH to the Abis-TCH. In case of intra-cell handover this is done after receipt of the ESTABLISH INDICATION for the target TCH.

A30808-X3247-M41-3-7618

Information System


1.2.10

Handover due to BSS Resource Management Criteria (Traffic Handover)

1.2.10.1

Successful Handover due to BSS Resource Management Criteria (Traffic Handover), FR Call

BTSold

MS

BTSnew

BSC

MSC

Call in progress... Expiry TRFCT*

UI (MEAS REP) SACCH

BSC detects that the traffic load in the BTS old exceeds the threshold TRFHITH

UI (MEAS REP) SACCH

UI (MEAS REP) SACCH

UI (MEAS REP) SACCH

SET ATTRIBUTE **

UI (MEAS REP)

(Traffic Handover enabled)

SACCH

SET ATTRIBUTE ACK Start TRFHOT Traffic Handover enabled in the BTS (m=1) *** BWHCI (cause: traffic)

ATTCHSEI (1.) ATINHIRC (9.) If last TCH start AALTCHTI (1.) CHNAV (New TCH) Start TTRAU


Start T_MSRFPCI DATRQ (HO CMD) I (HO CMD) FACCH

Start T8 AININIRH (9.) AOUINIRH (9.)

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125


MS

Information System

BTSold

BTSnew

MSC

BSC

HO ACCESS FACCH

Start T3124

HO ACCESS HANDO

FACCH

UI (PHYS INFO)

Stop TTRAU FACCH

Stop T3124 SABM

Start T3105

FACCH

Stop T3105 ESTIN

UA FACCH

I (HO CMP)

TNTCHCL (1.) DATIN (HO CMP)

FACCH

Stop T8 SINTHINT (9.) SININIRH (9.) SOUINIRH (9.) SINHOBSC (12.) MRPCI DT1 (HOPER) Stop T_MSRFPCI

(cause: distance)

SUCTCHSE (1.) RELRQ RELCN RCHRL (Old TCH) RCHRA MTCHBUTI (1.) (stop) AALTCHTI (1.) (stop)


126

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Information System

(*) (**)

(***)


Note: TRFCT represents a periodic cycle in which the BSC checks the traffic load in all its cells. The message SET ATTRIBUTE is sent via the Abis O&M channel (LPDLM, SAPI 62) and enables the traffic handover for the whole BTS. This means that the BTS makes the traffic handover decision for all calls currently busy in the cell and starts the timer TRFHOT (when it expires, the BTS makes the next handover decision for all calls that are busy at that point of time). This message flow just shows one single call for which the traffic handover was triggered and succesfully completed. The first traffic handover decision after the enabling of traffic handover in the BTS is based on the value m=1. m is an internal counter which is used in the calculation process of the traffic handover decision and which supports a mechanism for a dynamic decrease of the traffic handover margin for subsequent traffic handover decisions. For further details, please refer to the associated feature description for traffic handover!

A30808-X3247-M41-3-7618

127


1.2.10.2

Information System

Unsuccessful Inter-Cell Handover due to BSS Resource Management Criteria (Traffic Handover), traffic load in Target Cell exceeds the threshold TRFLTH

BTSnew

BTSold

MS

BSC

MSC

Call in progress... Expiry TRFCT*

UI (MEAS REP) SACCH

BSC detects that the traffic load in the BTS old exceeds the threshold TRFHITH

UI (MEAS REP) SACCH

UI (MEAS REP) SACCH

UI (MEAS REP) SACCH

SET ATTRIBUTE ** (Traffic Handover enabled)

UI (MEAS REP) SACCH

SET ATTRIBUTE ACK Start TRFHOT Traffic Handover enabled in the BTS (m=1) ***

BWHCI***

.. .. .

(cause: traffic)

.

.. .. . .

BSC detects that the traffic load in the target cell is above the threshold (TRFLTH) NHOINRHA (3.)

Expiry TRFHOT Next Traffic Handover decisson (m=2)

BWHCI**** (cause: traffic)

BSC detects that the traffic load in the target cell is above the threshold (TRFLTH) NHOINRHA (3.)

Call in continuation...

128

A30808-X3247-M41-3-7618

Information System

(*)


Note: TRFCT represents a periodic cycle in which the BSC checks the traffic load in all its cells.

(**)

The message SETATTRIBUTE is sent via the Abis O&M channel (LDDLM, SAPI 62) and enables the traffic handover for the whole BTS. This means that the BTS makes the traffic handover decision for all calls currently busy in the cell and starts the timer TRFHOT (when it expires, the BTS makes the next handover decision for all calls that are busy at that point of time). This message flow just shows one single call for which triggered and succesfully completed. (***) The first traffic handover decision after the enabling of traffic handover in the BTS is based on the value m=1. m is an internal counter which is used in the calculation process of the traffic handover decision and which supports a mechanism for a dynamic decrease of the traffic handover margin for subsequent traffic handover decisions. For further details, please refer to the associated feature description for traffic handover! (****) The traffic handover decision after the first expiry of TRFHOT is based on the value m=2. This margin is dynamically decreased with every expiry of TRFHOT. For further details, please refer to the associated feature description for traffic handover!

A30808-X3247-M41-3-7618

129


1.2.11 1.2.11.1

Information System

Queuing & Preemption Queuing: Queued Assignment Request for FR TCH Is Served Before T11 Expiry, Directed Retry Enabled But No Target Cell Available, Preemption Disabled or Not Allowed for the Requesting Call

MS

BTS

BSC

MSC

All TCHs in the BTS are busy... DT1 (ASS REQ) (queuing allowed indicator=allowed)


FHREQ BWHCI (cause: forced, no target cell included)

NHOINRHA (1.) DT1 (QUIND) Start T11

MDURTCRQ (1.) (start) DT1 (PROGRES) DATRQ (PROGRES) I (PROGRES) SDCCH

BTS congestion ends during runtime of T11, 1 TCH becomes idle again... Stop T11 PHCRQ

PHCCN

MDURTCRQ (1.) (stop) MTCHBUTI (1.) (start)

CHNAV Start TTRAU

CHNAK



130

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Information System


MS

BTS

BSC

MSC

SABM ESTIN

FACCH

UA TNTCHCL (1.)

FACCH

I (ASS CMP) FACCH

DATIN (ASS CMP) DT1 (ASS COM)

MRPCI


Stop T_MSRFPCI

Call setup completion ...

(**)


A30808-X3247-M41-3-7618

131


1.2.11.2

i

Information System

Queuing: Queued Assignment Request for FR TCH is Discarded from the Queue Before T11 Expiry Due to an Incoming FR Assignment Request with Higher Priority Directed Retry Enabled But No Target Cell Available, Preemption Disabled or Not Allowed for the Requesting Call The blue colour indicates the events related to the second (high priority) call.

MS

BTS

BSC

MSC

All TCHs in the BTS are busy... DT1 (ASS REQ)

FHREQ

(queuing allowed indicator=allowed)


BWHCI (cause: forced, no target cell included)

First call: low priority

NHOINRHA (1.)

DT1 (QUIND)

Start T11 (low prio call) MDURTCRQ (1.) (start) DATRQ (PROGRES)

I (PROGRES)

DT1 (PROGRES)

SDCCH

All places in the queue are occupied after the first call... DT1 (ASS REQ)*

FHREQ* Second call: high priority

ATTCHSEI (1.)* ATCHSMBS (1.)* TASSATT (2.)*

BWHCI* (Cause: forced, no target cell included)

Stop T11 (low prio call) NMSGDISQ (1.) MDURTCRQ (1.) (stop) NHOINRHA (1.) Start T11* (high prio call) MDURTCRQ (1.) (start)*

132

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Information System


MS

BTS

BSC

MSC DT1 (QUIND)* DT1 (ASS FAI)

(Cause: no radio resource available)

TASSFAIL (8.) DT1 (PROGRES)* DATRQ (PROGRES)* I (PROGRES)* SDCCH

High priority call remains queued...*

(*)

Events related to second (high priority) call

A30808-X3247-M41-3-7618

133


1.2.11.3

Information System

Queuing: Queued Assignment Request for FR TCH Is Discarded from Queue Due to T11 Expiry, Directed Retry Enabled But No Target Cell Available, Preemption Disabled or Not Allowed for the Requesting Call

MS

BTS

BSC

MSC

All TCHs in the BTS are busy... DT1 (ASS REQ)

FHREQ



BWHCI (cause: forced, no target cell included)

NHOINRHA (1.) DT1 (QUIND) Start T11 MDURTCRQ (1.) (start) DT1 (PROGRES)

DATRQ (PROGRES) I (PROGRES) SDCCH

Expiry T11 NMSGDISQ (1.) MDURTCRQ (1.) (stop) DT1 (CL REQ) NRCLRREQ (22.)


DT1 (CL CMD) NRCLRCMD (1.)


Release of the queued context...

134

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Information System


1.2.11.4

MS

Queuing: Queued Handover Request for FR TCH Is Served Before TQHO Expiry, Preemption Disabled or Not Allowed for the Requesting Call

BSCnew

BTS

MSC

BSC old

All TCHs in the BTS are busy... DT1 (HO RQD) CR (HO REQ) (queuing allowed indicator=not allowed)*

ATTCHSEI (1.) ATCHSMBS (1.) CREF (HO FAI) (cause: no radio resource available)

NRINHDFL CR (HO REQ) (queuing allowed indicator=allowed)*

ATTCHSEI (1.) ATCHSMBS (1.) CC (QUIND) Start TQHO MDURTCRQ (3.) (start)

BTS congestion ends during runtime of TQHO, 1 TCH becomes idle again... Stop TQHO MDURTCRQ (3.) (stop) CHNAV Start TTRAU CHNAK

DT1 (HO RAC; HO CMD)

Start T_MSRFPCI DT1 (HO CMD; HO CMD)

Completion of Handover procedure...

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(*)

136

Information System

In case of MSC-controlled handover the MSC cyclically attempts the HANDOVER REQUEST procedure towards all target cells previously received in the HANDOVER REQUIRED message from the originating BSC. For the first cycle, the SIEMENS MSC generally sets the ‚queuing allowed indicator‘ to ‚not allowed‘. If in this first cycle the request for radio resoucres fails for all target cells, the SIEMENS MSC repeats the cycle again, this time, however, with the ‚queuing allowed indicator‘ set to ‚allowed‘. This is done to avoid an unnecessary delay in the handover execution and in order to use the queuing mechanism as the very last measure to rescue a call.

A30808-X3247-M41-3-7618

Information System


1.2.11.5

i

Queuing: Queued Handover Request for FR TCH Is Discarded from the Queue Before TQHO Expiry Due to an Incoming FR Call with Higher Priority, Preemption Disabled or Not Allowed for the Requesting Calls The blue colour indicates the events related to the high priority call.

BSCnew

BTS

MS

MSC

BSC old

All TCHs in the BTS are busy... CR (HO REQ) (queuing allowed indicator=allowed)

ATTCHSEI (1.) ATCHSMBS (1.) CC (QUIND) Start TQHO MDURTCRQ (3.) (start)

All places in the queue are occupied after the handover request... DT1 (ASS REQ)* ATTCHSEI (1.)* ATCHSMBS (1.)* TASSATT (2.)* FHREQ* High priority call

BWHCI* (cause: forced, no target cell included)

Stop TQHO (low prio call) NMSGDISQ (3.) MDURTCRQ (3.) (stop) NHOINRHA (1.) Start T11* (high prio call) MDURTCRQ (1.) (start)* DT1 (QUIND)* RLSD (HO FAI) NRINHDFL

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137


Information System

BSC new

BTS

MS

MSC

BSC old

RLC DT1 (PROGRES)* DATRQ (PROGRES)* I (PROGRES)* SDCCH

High priority call remains queued...*

(*)

138

Events related to high priority call

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Information System


1.2.11.6

MS

Queuing: Queued Handover Request for FR TCH Is Discarded from the Queue Due to TQHO Expiry, Preemption Disabled or Not Allowed for the Requesting Calls

BTS

BSCnew

MSC

BSC old

All TCHs in the BTS are busy...

CR (HO REQ) ATTCHSEI (1.) ATCHSMBS (1.)


CC (QUIND) Start TQHO MDURTCRQ (3.) (start)

Expiry TQHO NMSGDISQ (3.) MDURTCRQ (3.) (stop) RLSD (HO FAI) NRINHDFL


RLC

Release of the queued context...

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1.2.11.7

i

Information System

Preemption: Successful Forced Inter-Cell Handover Due to Preemption, Preempted Assignment Request and Preempting Call Are Both FR The blue colour indicates the events related to preempting call.

BTSold

MS

BTSnew

BSC

MSC

All TCHs in the old BTS are busy... DT1 (ASS REQ)* (preemption allowed indicator=allowed)


FHREQ BWHCI (cause: forced, BTSnew included)

CHNAV

ATTCHSEI (1.) ATINHIRC (11.) If last TCH start AALTCHTI (1.) MTCHBUTI (1.) (start)

CHNAK DATRQ (HO CMD) I (HO CMD) FACCH

Start T8 AININIRH (11.) AOUINIRH (11.)

Continuation of inter-cell handover procedure for preempted call... I (HO CMP) FACCH

DATIN (HO CMP) Stop T8 SININIRH (11.) SINTHINT (11.) SOUINIRH (11.) SINHOBSC (16.)

140

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Information System


BTSold

MS

BTSnew

MSC

BSC HOPER

MRPCI

(cause: Preemption)

RELRQ RELCN RCHRL RCHRA PHCRQ*

MTCHBUTI (stop)

MTCHBUTI (start)* PHCCN* CHNAV* Start TTRAU*

CHNAK*

Start T_MSRFPCI* DATRQ (ASS CMD)* I (ASS CMD)* SDCCH

Start T10*

Completion of Assignment procedure for preempting call...

(*)

Events related to preempting call

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1.2.11.8

i

Information System

Preemption: Forced Release of Preempted Call Due to Lack of Target Cell for Forced Inter-Cell Handover Procedure, Preempted and Preempting Call Are Both FR The blue colour indicates the events related to preempting call.

BTSnew

BTSold

MS

MSC

BSC

All TCHs in the old BTS are busy... DT1 (ASS REQ)* (preemption allowed indicator=allowed)


FHREQ BWHCI (cause: forced, no target cell)

NHOINRHA (1.) DT1 (CL REQ) NRCLRREQ (7.)

(cause: preemption)

DT1 (CL CMD) (cause: preemption)

NRCLRCMD (1.)

Release of preempted call... PHCRQ* MTCHBUTI (start)* PHCCN* CHNAV* Start T10* CHNAK* Start T_MSRFPCI* DATRQ (ASS CMD)* I (ASS CMD)* SDCCH

Start T10*

Completion of assignment procedure for preempting call... (*)

142


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Information System


1.2.11.9

Preemption: Successful Forced Inter-BSC Handover Due to Preemption, Preempting Handover Request and Preempted Call Are Both FR, Originating BSC of the Preempting Handover Request and Target BSC for the Forced Handover Are the Same The blue colour indicates the events related to preempting call.

i MS

BTSold

BSC old

MSC

BSCnew

BTSnew

All TCHs in the old BTS are busy... DT1 (HO RQD)* CR (HO REQ)* (preemption indicator=allowed)

ATTCHSEI (1.)* ATCHSMBS (1.)* FHREQ BWHCI DT1 (HO RQD)

(cause: forced, external target cell included)

(cause: Preemption

CR (HO REQ) (cause: Preemption)

Start T7 ATTCHSEI (1.) If last TCH start AALTCHTI (1.) CHNAV CHNAK CC (HO RAC; HO CMD) DT1 (HO CMD; HO CMD) Stop T7

Start T_MSRFPCI

Start Trr7 (***)

ATINBHDO (10.) DATRQ (HO CMD) I (HO CMD) FACCH

Start T8

Continuation of inter-BSC handover procedures for preempted call... I (HO CMP) FACCH

SUCTCHSE (1.)

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MS

Information System

BTSold

BSCold

MSC

BSCnew

BTSnew

DT1 (HO CMP) Stop Trr7 (***) DT1 (CL CMD) Stop T8


SUINBHDO (10.) NRCLRCMD (3.) RELRQ

RELCN DT1 (CL CMP) RCHRL RLSD RCHRA MTCHBUTI (1.)* RLC CHNAV* Start TTRAU* CHNAK* Start T_MSRFPCI* Stop TTRAU*

CC (HO RAC; HO CMD)* DT1 (HO CMD; HO CMD)* Start Trr7 (***)

Start T8 ATINBHDO (*) I (HO CMD)* FACCH

Continuation of preempting incoming MSC-controlled handover procedure...

(*)


(**)

TTRAU is stopped when the BTS receives the (idle) TRAU frames from the TRAU. This happens when the BSC throughconnects the Asub-TCH to the Abis-TCH. In case of inter-BSC handover this is done on the CHANNEL ACTIVATION ACKNOWLEDGE for the TCH in the target BTS. Trr7 is an MSC timer which supervises the receipt of a HO CMP after transmission of a HO CMD.

(***)

144

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Information System


1.2.12 1.2.12.1

HSCSD Successful HSCSD Call, Mobile Originating, 3 TCHs Used

MS

BTS CHNREQ

BSC

MSC

CHNRD

RACH

NATTSDPE NACSUCPR (3.) ATIMASCA (4.) If last SDCCH start ASDCALTI CHNAV (SDCCH) CHNAK IACMD (IMASS)

UI (IMASS) AGCH


NTDMAGCH (1.) SABM (CMSREQ)

ESTIN (CMSREQ)

SDCCH

UA NSUCCHPC (4.)

SDCCH

CR (CL3I; CMSREQ)

MRPCI CC (CICMD)

ENCRY (CIMCMD)

I (CIMCMD) SDCCH

I (CLAMCH) SDCCH

DATIN (CLAMCH) I (CIMCMP) DATIN (CIMCMP)

SDCCH

SETUP

DATIN (SETUP)

SDCCH

DT1 (CLUPD) DT1 (CICMP)

DT1 (SETUP)

DATRQ (CPROC)

I (CPROC)

DT1 (CPROC) DT1 (ASREQ)

SDCCH

ATTCHSEI (1.) (*) TASSATT (2.) If last TCH start AALTCHTI (1.)

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Information System

MS

BTS

BSC

MSC

PHCRQ MTCHBUTI (1.) (start) (*) PHCCN

CHNAV (mCH) (**) Start TTRAU

(activation type: related to normal assignment procedure)

Start TTRAU

(activation type: related to multislot configuration)

Start TTRAU


CHNAV (sCH1) (**)

CHNAV (sCH2) (**)

CHNAK (mCH) (**) Start T_MSRFPCI CHNAK (sCH1) (**) Start T_MSRFPCI CHNAK (sCH2) (**) Start T_MSRFPCI DATRQ (ASS CMD) Stop TTRAU (***) I (ASS CMD) SDCCH

SABM ESTIN

FACCH

UA FACCH

I (ASS CMP) FACCH

TNTCHCL (1.) TNMSCNCL (3.) DATIN (ASS CMP)

DT1 (ASS CMP)

SUCTCHSE (1.) (*) TASSSUCC (2.)

146

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Information System


MS

BTS

BSC

MSC

MRPCI (mCH) (**) Stop T_MSRFPCI MRPCI (sCH1) (**) Stop T_MSRFPCI MRPCI (sCH2) (**) Stop T_MSRFPCI RELRQ RELCN RELCHRL RCHRA ASDCALTI (stop) DT1 (ALERT) DATRQ (ALERT)

I (ALERT)

DT1 (CONNECT)

FACCH

DATRQ (CONNECT)

I (CONNECT) FACCH

I (CONACK) FACCH

DATIN (CONACK)

DT1 (CONACK)

Call phase ...

(*)

Note: This counter counts as many events as TCHs are used for the HSCSD call.

(**)

mCH = main channel sCH1 = 1. secondary channel sCH2 = 2. secondary channel

(***)


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1.2.12.2

Information System

Successful Inter-cell Handover of an HSCSD Call (3 TCHs Used), Intra-BSC

BTSold

MS

BTSnew

BSC

MSC


UI (MEAS REP) SACCH

UI (MEAS REP) SACCH

Start THORQST


ATTCHSEI (1.) (****) ATINHIRC (*) If last TCH start AALTCHTI (1.) CHNAV (mCH) (**) Start TTRAU


CHNAV (sCH)1 (**) Start TTRAU


CHNAV (sCH2) (**) Start TTRAU


CHNAK (mCH) (**) Start T_MSRFPCI CHNAK (sCH1) (**) Start T_MSRFPCI CHNAK (sCH2) (**) Start T_MSRFPCI DATRQ (HO CMD) I (HO CMD)

Start T8

FACCH


HO ACCESS FACCH

Start T3124 HO ACCESS HANDO

FACCH

Stop TTRAU (**)

148

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Information System

MS


BTSold

BTSnew

MSC

BSC

UI (PHYS INFO) FACCH

Stop T3124

Start T3105 SABM

FACCH

Stop T3105 ESTIN

UA FACCH

I (HO CMP)

TNTCHCL (1.) TNMSCNCL (3.) DATIN (HO CMP)

FACCH

Stop T8 SINTHINT (*) SININIRH (*) SOUINIRH (*) SINHOBSC (*) DT1 (HOPER) SUCTCHSE (1.) (****)

(with HO cause)

MRPCI (mCH) (**) Stop T_MSRFPCI MRPCI (sCH1) (**) Stop T_MSRFPCI MRPCI (sCH2) (**) Stop T_MSRFPCI

RELRQ RELCN

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Information System

BTSold

MS

BTSnew

BSC

MSC

RCHRL RCHRL RCHRL RCHRA (*****)

MTCHBUTI (1.) (stop) RCHRA MTCHBUTI (1.) (stop) RCHRA MTCHBUTI (1.) (stop) AALTCHTI (1.) (stop)


(*)


(**)


(***)


(****)


(*****) Note: The number of the channels to be released in the old cell depends on the number of TCHs used for the HSCSD call in the old cell (the number of TCHs used can change during the handover procedure, depending on the number of channels available).

150

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Information System


1.2.12.3

Forced Intra-cell Handover During HSCSD Assignment Procedure

MS

BTS

BSC

MSC

HSCSD call setup... (see 1.2.12.1) Not enough adjacent TCHs

DT1 (ASREQ) (****) ATTCHSEI (1.) (*) TASSATT (2.) If last TCH start AALTCHTI (1.) CHNAV (new TCH)

Start TTRAU CHNAK Start T_MSRFPCI DATRQ (ASS CMD)

I (ASS CMD)

Start T10

Old FACCH

ATINHIAC (12.) SABM ESTIN

New FACCH

UA

Stop TTRAU (***)

TNTCHCL (1.)

New FACCH


DATIN (ASS CMP) Stop T10 SINTHITA (12.) SINHOBSC (16.) MRPCI Stop T_MSRFPCI RELRQ DT1 (HOPER) RELCN


SUCTCHSE (1.)

RELCHRL RCHRA MTCHBUTI (1.) (stop) AALTCHTI (1.) (stop)

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MS

Information System

BTS

BSC

MSC

PHCRQ (****) MTCHBUTI (1.) (start) (*) (****) PHCCN (****) CHNAV (mCH) (**) (****) Start TTRAU

(activation type: related to normal assignment procedure)

CHNAV (sCH1) (**) (****) Start TTRAU


CHNAV (sCH2) (**) (****) Start TTRAU


HSCSD call setup continuation... (see 1.2.12.1)

(*)


(**)


(***)

TTRAU is stopped when the BTS receives the (idle) TRAU frames from the TRAU. This happens when the BSC throughconnects the Asub-TCH to the Abis-TCH. In case of TCH Assignment this is done on transmission of the ASSIGNMENT COMMAND. Events related to HSCSD TCH request.

(****)

152

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Information System


1.2.13 1.2.13.1

Signalling Transactions without TCH Successful Location Update (Phase 2 MS)

MS

BTS CHNREQ

BSC

MSC

CHNRD

RACH


UI (IMASS)


AGCH

NTDMAGCH (1.) SABM (LUREQ)

ESTIN (LUREQ)

SDCCH

UA


SDCCH

CR (CL3I; LUREQ)


CC

Optional: Authentication & Ciphering Procedure...(see 1.2.1.1) DATRQ (LUACC)

I (LUACC)

DT1 (LUACC)

SDCCH

I (TRCMP)

DATIN (TRCMP)

SDCCH

DT1 (TRCMP) DT1 (CL CMD)


DT1 (CL CMP)

I (CHREL) SDCCH

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MS

Information System

BTS

BSC

MSC

DESAC RLSD RLC

DISC RELIN

SDCCH

UA SDCCH

RCHRL (SDCCH) RCHRA ASDCALTI (stop) MBUSYSSP (5.) (accumulation)

154

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Information System


1.2.13.2

Successful Location Update (2G/3G (GSM/UMTS) Multirat MS)

MS

BTS CHNREQ

BSC

MSC

CHNRD

RACH


UI (IMASS)


AGCH

NTDMAGCH (1.) SABM (LUREQ)

ESTIN (LUREQ)

SDCCH

UA


SDCCH


CR (CL3I; LUREQ) CC

CLCH DATIN (CLCH) DT1 (CLUPD) UTRANCC DATIN (UTRANCC)

Optional: Authentication & Ciphering Procedure...(see 1.2.1.1)

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155


MS

Information System

BTS

BSC

MSC DT1 (LUACC)

DATRQ (LUACC)

I (LUACC) SDCCH

I (TRCMP)

DATIN (TRCMP)

SDCCH

DT1 (TRCMP) DT1 (CL CMD)


DT1 (CL CMP)

I (CHREL) SDCCH

DESAC RLSD RLC

DISC SDCCH

RELIN UA SDCCH


156

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Information System


1.2.13.3

Successful IMSI Detach (Phase 2 MS)

MS

BTS CHNREQ

BSC

MSC

CHNRD

RACH


UI (IMASS)


AGCH

NTDMAGCH (1.) SABM (IMDETIN) SDCCH

ESTIN (IMDETIN)

UA


SDCCH

CR (CL3I; IMDETIN)


Optional: Authentication & Ciphering Procedure... (see 1.2.1.1) DATRQ (CHREL)

I (CHREL)

CREF

SDCCH

DESAC DISC RELIN

SDCCH

UA SDCCH


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1.2.13.4

Information System

Successful Supplementary Service (SS) Management Procedure via Subscriber-Controlled Input (SCI)

MS

BTS CHNREQ

BSC

MSC

CHNRD

RACH


UI (IMASS) AGCH

NTDMAGCH (1.) I (CMSREQ) SDCCH

(CM Service type: Supplementary Service Activation)


ESTIN (CMSREQ) (CM Service type: Supplementary Service Activation)

Stop T3101 NSUCCHPC (6.) NASUSDPE

MRPCI

ENCRY (CIMCMD)

I (CIMCMD)

CR (CL3I; CMSREQ)

CC (CICMD)

SDCCH

I (CLAMCH) DATIN (CLAMCH)

SDCCH

DT1 (CLUPD) MRPCI Stop T_MSRFPCI I (CIMCMP) SDCCH

158

DATIN (CIMCMP)

DT1 (CICMP)

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Information System


MS

BTS I (REGISTER)

SDCCH

BSC DATIN (REGISTER)

(SS code, operation code, service)


DT1 (REGISTER) (SS code, operation code, service)

DATRQ (REL CMP)

I (REL CMP)

MSC

DT1 (REL CMP)

SDCCH


DATRQ (CHREL)

I (CHREL) SDCCH

DESAC RLSD RLC

DISC

RELIN

SDCCH

UA SDCCH


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1.2.13.5

Information System

Successful USSD (Unstructured Supplementary Service Data) Management Procedure via (SCI)

MS

BTS CHNREQ

BSC

MSC

CHNRD

RACH


UI (IMASS) AGCH

NTDMAGCH (1.) I (CMSREQ) SDCCH

(CM Service type: Supplementary Service Activation)


ESTIN (CMSREQ) (CM Service type: Supplementary Service Activation)

Stop T3101 NSUCCHPC (6.) NASUSDPE

MRPCI

ENCRY (CIMCMD)

I (CIMCMD)

CR (CL3I; CMSREQ)

CC (CICMD)

SDCCH

I (CLAMCH) DATIN (CLAMCH)

SDCCH

DT1 (CLUPD) MRPCI Stop T_MSRFPCI I (CIMCMP) SDCCH

160

DATIN (CIMCMP)

DT1 (CICMP)

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Information System


MS

BTS I (REGISTER)

SDCCH

BSC

MSC

DATIN (REGISTER)



NSUSDSUS (*)

DT1 (REGISTER) (SS code, operation code, service)

DT1 (REL CMP) DATRQ (REL CMP) I (REL CMP) SDCCH


DATRQ (CHREL)

I (CHREL) SDCCH

DESAC RLSD RLC

DISC

RELIN

SDCCH

UA SDCCH

RCHRL (SDCCH) RCHRA ASDCALTI (stop) MBUSYSSP (3.) (*) (accumulation)

(*)

NSUSDSUS and MBUSYSSP subcounter 3 are only triggered if the database flag TRANSPM (BSC object) is set to TRUE. If this flag is set to FALSE, NSUSDSUS is not triggered at all and MBUSYSSP is triggered for subcounter 4.

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161


1.2.13.6

Information System

Unsuccessful Immediate Assignment Procedure, No SDCCH Available

MS

BTS CHNREQ

BSC

MSC

CHNRD

RACH

NATTSDPE ATSDCMBS NACSUCPR (3.), (1.) (**) ATIMASCA (*) IACMD (IMASSRJ)

UI (IMASSRJ) AGCH

Start T3122

NTDMAGCH (1.)

TACCBPRO (2.) NACSUCPR (2.)

.. .. . Expiry T3122 CHNREQ (***) RACH

(*) (**) (***)

162

Subcounter depends on the access cause Subcounter (1.) is only increased if the access cause is ’answer to paging’. T3122 is started in the MS on receipt of an IMMEDIATE ASSIGNMENT REJECT. When it expires, the MS attempts another access to the cell.

A30808-X3247-M41-3-7618

Information System


1.2.13.7

Unsuccessful Immediate Assignment Procedure, No AGCH Available (AGCH Overload)

MS

BTS

BSC

CHNREQ

MSC

CHNRD

RACH

NATTSDPE, NACSUCPR (3.), (1.) (**) ATIMASCA (*) If last SDCCH start ASDCALTI CHNAV (SDCCH) CHNAK Start T_MSRFPCI IACMD (IMASS) No AGCH available, IMASS discarded

Start T3101 TACCBPRO (2.) SUIMASCA (*) NACSUCPR (2.)

NTDMAGCH (3.) DELIN (*) Stop T3101 NACSUCPR (2.) decreased by 1 ASDCALTI (stop)

(*)

Subcounter depends on the access cause.

(**)

Subcounter (1.) is only increased if the access cause is ’answer to paging’.

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163


1.2.13.8

Information System

Unsuccessful Immediate Assignment Procedure, assigned SDCCH is not seized by the MS (Phantom RACH Scenario)

MS

BTS CHNREQ

BSC

MSC

CHNRD

RACH

NATTSDPE, NACSUCPR (3.), (1.) (**) ATIMASCA (*) If last SDCCH start ASDCALTI CHNAV (SDCCH) CHNAK Start T_MSRFPCI IACMD (IMASS)

UI (IMASS)

Start T3101

AGGH


Expiry T3101 RCHRL (SDCCH) RCHRA ASDCALTI (stop) MBUSYSSP (n.) (accumulation)

(*) (**)

164

Subcounter depends on the access cause. Subcounter (1.) is only increased if the access cause is ’answer to paging’.

A30808-X3247-M41-3-7618

Information System


1.2.13.9

BTS Discards Invalid RACH Messages

MS

BTS

CHNREQ RACH

BSC

Level of received CHANNEL REQUEST is below the threshold RACHBT NINVRACH (1.)

MS

BTS

CHNREQ RACH

BSC

Timing advance value determined from the received CHANNEL REQUEST exceeds the threshold EXCDIST NINVRACH (2.)

A30808-X3247-M41-3-7618

165


1.2.13.10

Information System

Immediate Assignment Procedure for Abis Link Configured via Satellite Link Abis link with high propagation delay

MS

BTS

BSC

MSC

CHNREQ RACH

CH

NR

D

NATTSDPE NACSUCPR (3.) ATIMASCA (4.) If last SDCCH start ASDCALTI

)

CH

C SD

V(

A HN

)

C

) (*

S AS

MD


C IA

Start

Start T3101

(IM

CH

NA

K

UI (IMASS) AGCH

Call / Transaction Setup Continuation ...

(*)

166

When for the BTSM object subordinate to the serving BTS, the parameter LPDLMSAT (BTSM object) is set to TRUE, the BSC sends the IMMEDIATE ASSIGNMENT message to the BTS immediately after the transmission of the CHANNEL ACTIVATION message without waiting for the CHANNEL ACTIVATION ACKNOWLEDGE. This is done to avoid additional Immediate Assignment signaling delay and, as a consequence. unnecessary RACH retransmissions from the mobile stations.

A30808-X3247-M41-3-7618

Information System

1.2.13.11


Paging Overload - BTS discards a PAGING REQUEST Message

MS

BTS

BSC

MSC UDT (PAGIN)

TCMSGREC

PGCMD

TACCBPRO (1.)

No place in any paging queue available - the BTS discards the PAGING REQUEST * NTDMPCH (3.) OVERLOAD (cause: CCCH overload)

Start T17 **

BSC starts to discard all pagings towards this BTS **

*

**

Each paging queue place in the BTS can be seized by one PAGING REQUEST message (PAGREQ) which itself can contain the mobile identities (IMSI or TMSI) of up to 3 mobile subscribers simultaneously. This means that the PAGING REQUEST message can contain the mobile identities of up to 3 PAGING COMMANDS (PGCMD) that were received from the BSC before. If the BTS discards a PAGING REQUEST due to lack of paging queue places, NTDMPCH (3.) is increased by as many counts as mobile identities (IMSI or TMSIs) were contained in the discarded PAGING REQUEST message! In other words, if the discarded PAGING REQUEST contains e.g. 3 TMSIs, then NTDMPCH (3.) is increased by 3. The BSC starts T17 and discards all new PAGING COMMANDS to the BTS only if BTS overload handling is enabled in the BSC (BTSOVLH=TRUE). The PAGING COMMANDS to the BTS are discarded as long as T17 runs.

A30808-X3247-M41-3-7618

167


1.2.14 1.2.14.1

Information System

Short Message Service Successful SMS Mobile Originating in Idle Mode (Phase 2 MS)

MS

BTS

BSC

MSC

CHNREQ CHNRD

RACH

NATTSDPE NACSUCPR (3.) ATIMASCA (6.) If last SDCCH start ASDCALTI CHNAV (SDCCH) CHNAK Start T_MSRFPCI IACMD (IMASS) UI (IMASS)

Start T3101

AGCH

TACCBPRO (2.) SUIMASCA NACSUCPR (2.) SABM (CMSREQ) ESTIN (CMSREQ)

SDCCH

UA

Stop T3101 SDCCH

NSUCCHPC (6.) NASUSDPE MRPCI

CR (CL3I; CMSREQ) CC

Stop T_MSRFPCI

Optional: Authentication & Ciphering Procedure... (see 1.2.1.1) DATRQ (TRCMD)

I (TRCMD)

DT1 (TRCMD)

SDCCH

SABM (SAPI 3)

ESTIN (SAPI 3)

SDCCH

UA (SAPI 3)

NSUCCHPC (7.)

SDCCH

I (TRCMP) SDCCH

168

DATIN (TRCMP)

DT1 (TRCMP)

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MS

BTS

I (CPDAT; RPDA) SDCCH

BSC

DATIN (CPDAT; RPDA)

SDCCH

DATRQ (CPDAT; RPAC)

I (CPDAT;RPAC)

DT1 (CPDAT; RPDA) DT1 (CPACK)

DATRQ (CPACK)

I (CPACK)

MSC

DT1 (CPDAT; RPAC)

SDCCH

I (CPACK)

DATIN (CPACK)

SDCCH

DT1 (CPACK) DT1 (CL CMD)

DATRQ (CHREL)

I (CHREL)

NRCLRCMD (2.)

SDCCH

DESAC DISC

RELIN

SDCCH

UA SDCCH

DT1 (CL CMP)

RELRQ RELCN RLSD RLC RCHRL (SDCCH) RCHRA ASDCALTI (stop) MBUSYSSP (2.) (accumulation)

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Information System

Successful SMS Mobile Terminating in Idle Mode (Phase 2 MS)

MS

BTS

BSC UDT (PAGIN)

PGCMD

UI (PAGREQ) PCH

CHNREQ

MSC

TACCBPRO (1.)

NTDPMAIN (1.) CHNRD

RACH

NATTSDPE NACSUCPR (1.), (3.) ATIMASCA (1.) If last SDCCH start ASDCALTI CHNAV (SDCCH) CHNAK Start T_MSRFPCI IACMD (IMASS)

UI (IMASS)

Start T3101

AGCH


SABM (PAGRES) SDCCH

ESTIN (PAGRES) UA

Stop T3101

SDCCH

NSUCCHPC (1.) NASUSDPE MRPCI Stop T_MSRFPCI

CR (CL3I; PAGRES) CC

Optional: Authentication & Ciphering Procedure...(see 1.2.1.1) DATIN (TRCMD)

I (TRCMD) SDCCH

SABM (SAPI 3) I (TRCMP)

ESTRQ (SAPI 3)

DT1 (TRCMD) DT1 (CPDAT; RPDA)

SDCCH

DATIN (TRCMP)

SDCCH

UA (SAPI 3)

DT1 (TRCMP)

ESTCN (SAPI 3)

SDCCH

NSUCCHPC (8.) I (CPDAT; RPDA)

DATRQ (CPDAT; RPDA)

SDCCH

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MS

BTS I (CPACK)

BSC

DATIN (CPACK)

SDCCH

I (CPDAT; RPAC) SDCCH

DT1 (CPDAT; RPAC) DT1 (CPACK) DT1 (CL CMD)

SDCCH

DATRQ (CHREL)

I (CHREL)

DT1 (CPACK)

DATIN (CPDAT; RPAC)

DATRQ (CPACK)

I (CPACK)

MSC

NRCLRCMD (2.)

SDCCH

DESAC DISC

RELIN

SDCCH

DT1 (CL CMP)

UA SDCCH

RLSD

RELRQ

RELCN

RLC


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1.2.14.3

Information System

Successful SMS Mobile Originating in Connected Mode (FR Call Ongoing)

MS

BTS

BSC

MSC

Call in progress... I (CMSREQ) FACCH

DATIN (CMSREQ) DT1 (CMSREQ) DT1 (CMSACC) DATRQ (CMSACC) I (CMSACC) FACCH

SABM (SAPI 3) SACCH

ESTIN (SAPI 3) UA (SAPI 3) SACCH

NSUCCHPC (15.)

I (CPDAT; RPDA) SACCH

DATIN (CPDAT; RPDA) DT1 (CPDAT; RPDA)

DATRQ (CPACK)

DT1 (CPACK) DT1 (CPDAT; RPAC)

I (CPACK) SACCH

DATRQ (CPDAT; RPAC)

I (CPDAT; RPAC) SACCH

DT1 (CPACK) SACCH

DATIN (CPACK)

DT1 (CPACK)


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1.2.14.4

Successful SMS Mobile Terminating in Connected Mode

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MS

BTS

BSC

MSC

Call in progress... DT1 (CPDAT; RPDA) ESTRQ (SAPI 3) SABM (SAPI 3) SACCH

UA (SAPI 3) SACCH

ESTCN (SAPI 3) NSUCCHPC (16.) DATRQ (CPDAT; RPDA) I (CPDAT; RPDA) SACCH

I (CPACK) SACCH

DATIN (CPACK) I (CPDAT; RPAC)

SACCH

DT1 (CPACK) DATIN (CPDAT; RPAC) DT1 (CPDAT; RPAC) DT1 (CPACK) DATRQ (CPACK)

I (CPACK) SACCH


174

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1.2.15 1.2.15.1

Advanced Speech Call Items (ASCI) Procedures VBS/VGCS Setup Initiated by fixed Dispatcher and Release By means of this procedure, performed for every cell involved in the Group Call Area (GCA), the BSC activates in the cell the common VBS/VGCH TCH. In the Message Flow below GCA contains bts1 and bts2 in BSC1 and bts1 and bts2 in the BSC2.

MS

bts1/bts2

BSC1

bts1/bts2

MSC

BSC2 CR (VBST) CR (VBST)

SCCP connection Group Call Control

CC (VBSA) CC (VBSA) DT1 (URLC) DT1 (URLC) CR (VARQ) cell identifier: bts 1 TASSATVS +1 in each cell incl. in GCA

CR (VARQ)

CR (VARQ)

One SCCP connection for each VBS/VGCS TCH i.e.for each call

cell identifier: bts 2

cell identifier: bts 1 TASSATVS +1 in each cell incl. in GCA

CR (VARQ) cell identifier: bts 2

ULFREE FACCH

ULFREE Notif/NCH

CHNAV

CHNAV

CHNAV

CHNAV

CHNAK

CHNAK

CHNAK

CHNAK

VBS/VGCS TCH

NCH

ULFREE

ULFREE

NOTCMD

NOTCMD command indicator ’start’

NNNOTNCH Notif/NCH

ULFREE

ULFREE

NOTCMD command indicator ’start’

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command indicator ’start’

NNNOTNCH NOTCMD command indicator ’start’

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MS

bts1/bts2

Information System

BSC1

bts1/bts2

BSC2

MSC

Notif/NCH NCH

Notif/NCH NCH

CC (VARE) cell identifier: bts 1

CC (VARE) SSI10 (SIT10)

cell identifier: bts 2


SSI10 (SIT10)

SSI 10 (SIT 10)


SSI 10 (SIT 10)

RELEASE initiated by fixed dispatcher... DT1 (CLCMD) DT1 (CLCMD) DT1 (CLCMD) NOTCMD

NOTCMD

command indicator ’stop’

CHREL DISC UA

CHREL

UDTRQ(CHREL)

DT1 (CLCMP)

DT1 (CLCMP) DESAC RCHRL

DESAC REHRL NOTCMD UDTRQ (CHREL)

NOTCMD UDTRQ(CHREL) DT1 (CLCMP)

DESAC DESAC

DESAC RCHRL

CHREL DISC UA CHREL DISC UA

command indicator ’stop’

UDTRQ(CHREL)

DISC UA

Release all res. DT1 (CLCMD) control SCCP connetion and associated VGCS/VBS TCH

DT1 (CLCMP)

RLSD RLSD

RLSD RLSD RLC RLC

RCHRA RCHRA DT1 (CLCMD) DT1 (CLCMP) RLSD RLC

RCHRA

RLSD RLSD

RCHRA

DT1 (CLCMD) DT1 (CLCMD)

Release SCCP connetion (Gr.. Call Control

RLSD RLC

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1.2.15.2

Succesful Uplink Allocation Procedure (1)

BTS

MS

BSC1

MSC

BSC2

BTS

ULFREE (2) ULFREE

VGRULF (3) FACCH

ULFREE

UPLINK ACCESS uplink voice group TCH

TALDC

VGCS UPLINK GRANT

DT1 (UPRQ)

downlink voice group TCH

DT1 (URA) UPBUS (ULBUSY) ULBUSY

DT1 (USC) (5) FACCH

SABM (TALKIND)

ESTIN (TALKIND)

UA (TALKIND)

UPBUS (ULBUSY)

DT1(URC) [TALKIND])

DATIN (CLCH) MRPCI DT1 (CLUPD) CR(ASREQ) CHNAV CHNAK DATRQ (ASCMD) ESTIN DATIN (ACOM) MRPCI UP_REL (6)

CC (ASCMP) SETPAR (7)

Conversation Phase...

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1. The listening subscriber may attempt to seize the Uplink common VGCS (TCH). When the MS is informed about the successful seizure it then moves on a dedicated channel (TCH) becomes the new talking subscriber.This is the typical talking subscriber change procedure. 2. The BSC sends this message to the BTS to indicate that the uplink of the VGCS channels becomes or is free. 3. vgcsULFreeTimer (VGRULF in BSC DB Object BTS [TIMER]). If no ASCI call is active the network provides an UPLINK FREE message on the main signalling channel periodically. The timer vgcsULFree Timer defines the repetition rate of sending this message. The timer will be stopped if an Uplink Access of a Mobile Station (MS) or an UPLINK Busy of the BSC was received. 4. Tgrant is a timer to define the repetition rate of sending the VGCS UPLINK GRANT message. In case of an ASCI call the network grants the uplink to one mobile station by sending a VGCS UPLINK GRANT message to the mobile station. After having sent this message the BTS starts TGRANT to repeat this message for as long as a counter has not reached the value of NRPGRANT. 5. With DT1 USC (Uplink Seize Cmd) the MSC informs a BSC that a MS belonging to another BSC area has successfully seized the uplink common VGCS channel. Then the BSS notifies its MSs that the channel is busy. 6. UPLINK RELEASE (BSC->BTS) sent on VGCS common channel to inform the BTS that the BSC has assigned a dedicated TCH to the talker in the same call during talker change procedure. 7. SET PARAMETER messages are sent from MSC where the MS is told that Uplink/Downlink is connected.

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1.2.15.3

FREE Uplink Procedure MS releases the dedicated channel (TCH). This happens when the talking subscriber wants to stop speaking. After this procedure, other MSs may attempt to seize the uplink common VGCS channel.

BTS

MS

MSC

BSC1

BTS

BSC2

Current talking subscriber releases its dedicated channel ULREL

DATIN(ULREL)

FACCH

ULFREE ULFREE FACCH

DT1 (UPRI) cause: call control DATRQ(CHREL)

DT1 (CLCMD) cause: call control

DT1 (URLC) cause: call control ULFREE

DT1 (CLCMD)

CHEL DESAC

RLSD

DISC

RLC

UA RELIN RCHRL RCHRA The other MSs may attempt to seize the uplink common VGCS channel, in order to talk.

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1.2.15.4

Information System

VGCS Setup initiated by Service Subscriber and Release

BTS

MS

BSC

MSC

CHNREQ CHNRD CHNAV CHNAK IAS CMSREQ

IACMD (IAS)

ESTIN (CMSREQ)

CR(CL3I[CMSREQ])

MRPCI CC (CICMD) ENCRY (CI CM)

SCCP connetion (res. controlling dedicated to the calling subscriber)

CICM CLCH

CICP

DATIN (CLCH) MRPCI

DT1 (CLUPD)

DATIN (CICP) DT1 (CICMP) SETUP PHCRQ

(1) DT1 (ASREQ)

PHCCN CHNAV CHNAK DATRQ (ASCMD) ASCMD UA

ESTIN DATIN (ACOM)

ACOM MRPCI

DT1 (ASCMP)

RELRQ RELCN RCHRL RCHRA

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BTS

MS

BSC

MSC CR (VBST)

SCCP connetion (Group Call Control)

CC (VBSA) CR (VARQ) CHNAV CHNAK ULBUSY

One SCCP connection (Res. Controlling) for each VGCS TCH, i.e. for each cell

UPBUS (ULBUSY)

FACCH

NOTCMD Notification/NCH command indicator: ’start’ SSI10 (SIT10)

CC (VARE)

CONNECT

(2)

DATIN (ULREL) ULFREE

UPFRE (ULFREE)

DT1 (UPRI)

FACCH

DATRQ (CREL)

CREL DISC (TCH call.subscr.)

DESAC

DT1 (CLCMD)

Release SCCP connection (Res.Controlling) and associated TCH

DT1 (CLMP) RLSD

UA

RELIN

RLC

RCHRL RCHRA

Calling subscriber terminates VGCS call Calling Subcriber Performs Talker Change Procedure... (see 1.2.15.2) TERMREQ

(4)

TERM

Release of the Talker TCH ... (see 1.2.15.3) Release all res. controlling SCCP connection and asociated VGCS THCs Release SCCP connections (Group Call Control)

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1. SETUP: The MSC is provided with details about the Voice Group Call. 2. CONNECT: Information to the mobile station of the calling subscriber that the VGCS is established with the related group call reference as the connected number. 3. The calling subscriber can terminate the call only if the calling subscriber has access to the uplink. 4. TERMINATION REQUEST: An authorized mobile station can send a TERMINATION REQUEST message to clear down the entire voice group call. To do this the mobile station must have access to the uplink.

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1.2.15.5

VGCS SETUP initiated by Service Subscriber (FAST CALL SETUP)

BTS

MS CHREQ

BSC

MSC

CHNRD CHNAV CHNAK

IAS SABM (ISETUP) (1)

IACMD (IAS)

ESTIN (ISETUP) CR (CL3I [ISETUP]) CC (CMSACC) DATRQ (CMSACC) DT1 (ASSREQ)

CMSACC

CR (VBST)

... (see 1.2.15.4)

(1)

This message is sent by the MS to the network in order to setup a group call immediately. No encryption and ciphering are performed to speed up the call setup procedure.

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1.2.15.6

MS

Information System

MTC During Ongoing VBS/VGCS Connection

MSC

BSC

BTS

Ongoing VBS/VGCS call, called party is a listening subscriber

UDTRQ (Notification FACCH)

Notif/FACCH

PAGIN IE call priority level

FACCH group call TCH

IE paging info is included

PGCMD

Succesful MTC SETUP ... (see 1.2.1.2)

If the PAGING message towards the BSC contains the emLPP priority level IE and if the emLPP priority level is greater or equal to the evalue set by the operator for an appropriate threshold (NOTFACCH in SET BSC) then a Notification / FACCH with paging information included is sent for each Voice Group Call channel active. If the paged MS is a listener of any ongoing ASCI call in the BSC then it should receive the Notification/FACCH message and switch to the incoming MTC call.

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1.2.15.7

VBS/VGCS Call during Ongoing Speech Call

MS

MSC

BSC

BTS

Ongoing MOC from ASCI service subscriber Incoming VBS/VGCS call UDTRQ (Notification FACCH)

Notif/FACCH FACCH

DISC cause value: pre-emption

FACCH TCH for speech call

IE Group call information is included

DISC

DT1 (DISC) cause value: pre-emption

DT1 (RELEAS) DATRQ (RELEAS) DATRQ (RELEAS)

Release of speech call

If the VBS/VGCS Assignment Request message contains the emLPP priority level IE and if the emLPP Priority level is greater than or equal to the value set by the operator for an appropriate threshold (NOTFACCH in SET BSC) then a Notification/FACCH with group call information included is sent a dedicated TCH occupied by speech call (MOC originated by ASCI subscriber, member of the incoming group call). If the originator of the ongoing MOC is a member of the incoming group call it should receive the Notification/FACCH message and switch the incoming group call. The MOC should be released.

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1.2.16 1.2.16.1

Information System

Inter System Handover (2G <--> 3G), circuit switched (CS) Successful Inter System Handover (2G --> 3G)

BTS

MS/ UE

2G+3G MSC

BSC

RNC

NodeB

UI (MEAS REP) BWHCI DT1 (HORQD) T7 start

lu Relocation Request lu Relocation Request ack

Activate new channels on UTRAN (3G) side

DT1 (HOCMD) T7 stop ATOISHDO

DATRQ (ISHUTRAN) I (HOCMD)

T3121 start

HO ACCESS

T3124 start

HO ACCESS RRC HO Detect lu Relocation Detect

T3124 stop

HO COMPLETE RRC HO Complete lu Relocation Complete

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MS/ UE


BTS

2G+3G MSC

BSC

RNC

NodeB

DT1 (CLCMD) T3121 stop SUOISHDO

DT1 (CLCMP) RELRQ RELCN RCHRL RCHRA RLSD RLC

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1.2.16.2

Information System

Unsuccessful Inter System Handover (2G --> 3G), loss of MS (loss of HOCMD), T3121 expiry

BTS

MS/ UE

2G+3G MSC

BSC

RNC

NodeB

UI (MEAS REP)

BWHCI DT1 (HORQD) lu Relocation Request lu Relocation Request ack


DT1 (HOCMD) ATOISHDO

DATRQ (ISHUTRAN) I (HOCMD)

T3121 start

T3121 expiry NRFLTCH

DT1 (CLREQ) NRCLRREQ

DT1 (CLCMD) NRCLRCMD

DT1 (CLCMP)

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MS/ UE


BTS

2G+3G MSC

BSC

RNC

NodeB

DATRQ (CREL) DESAC RELIN RCHRL RCHRA RLSD RLC Release new channels on UTRAN (3G) side

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1.2.16.3

MS/ UE

Information System

Unsuccessful Inter System Handover (2G --> 3G), No TCH available in Target UMTS Cell (3G)

BTS

2G+3G MSC

BSC

RNC

NodeB

UI (MEAS REP) BWHCI DT1 (HORQD) lu Relocation Request

T7 start

lu Relocation Failure

No TCHs available on UTRAN (3G) side

DT1 (HORRJ) T7 expiry NHOINRHA

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1.2.16.4

Unsuccessful Inter System Handover (2G --> 3G), Revision to old TCH, T3124 expiry

BTS

MS/ UE

2G+3G MSC

BSC

RNC

NodeB

UI (MEAS REP) BWHCI DT1 (HORQD)

lu Relocation Request lu Relocation Request ack


DT1 (HOCMD) ATOISHDO

DATRQ (ISHUTRAN) I (HOCMD) HO ACCESS HO ACCESS does not get through

HO ACCESS

T3124 start

T3124 expiry

SABM ESTIN UA I (HOFAIL) DATIN (HOFAIL) UNOISHDO

DT1 (HOFAI) lu Clear Command lu Clear Complete

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Release new channels on UTRAN (3G) side

191


1.2.16.5

Information System

Successful Inter System Handover (3G --> 2G)

NodeB

MS/ UE

2G+3G MSC

RNC

BTS

BSC

Event 2d: Meas Report [2d] Event 3a: Meas Report [3a] lu Relocation Required

CR (HOREQ) RQIISHDO

CHNAV CHNAK CC (HORAC,HCOM) lu Relocation Command RRC Handover Command Handover Command

HO ACCESS HO ACCESS HANDO DT1 (HODET) HO COMPLETE

ESTIN DATIN (HOCMP)

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MS/ UE


NodeB

RNC

2G+3G MSC

BTS

BSC

MRPCI DATRQ (CLEQ) DT1 (HOCMP) SUIISHDO lu Release Command Release old channels on UTRAN (3G) side

lu Release Complete

DATIN (CLCH) DT1 (CLUPD) MRPCI DATIN (UTRANCC) MRPCI

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1.2.16.6

MS/ UE

Information System

Unsuccessful Inter System Handover (3G --> 2G), No TCH available in Target GSM Cell (2G)

NodeB

RNC

2G+3G MSC

BSC

BTS

Event 2d: Meas Report [2d] Event 3a: Meas Report [3a] lu Relocation Required

CR (HOREQ) RQIISHDO No TCHs available on GSM (2G) side

CREF (HOFAI)

lu Relocation Required Reject

194

UNIISHDO

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1.2.17

1.2.17.1

Inter System Cell Reselection Procedure (2G <--> 3G), packet oriented (PO), intra SGSN inter system change Successful Inter System Cell Reselection Procedure (2G --> 3G) The inter system change from A/Gb mode to Iu mode takes place when a GPRSattached MS changes from A/Gb mode to GERAN or UTRAN IU mode. Depending on the GPRS mobility management state before the inter system change and whether the Routing Area (RA) is changed or not, one of the following procedures is initiated by the MS: – When an MS in STANDBY state changes to Iu mode inside the current RA, the MS shall follow the selective RA update procedures. – When an MS in STANDBY state changes to Iu mode and the RA changes, the MS shall initiate the Iu mode RA update procedure. – When an MS in READY state changes to Iu mode independent of whether the RA has changed or not, the MS shall initiate the Iu mode RA update procedure and afterwards initiate the Radio Access Bearers (RABs) by the Service Request procedure. The RA update procedure is either combined RA / LA update or only RA update. If the network operated in mode I, an MS that is both PS-attached and CS-attached shall perform the Combined RA / LA Update procedure. This concerns only idle mode (see 3GPP TS 23.122), as no combined RA / LA updates are performed during a CS connection. In the context of this specification, the terms RNS (or RNC) refer also to a GERAN BSS (or BSC) when serving an MS in Iu mode.

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MS/ UE

Information System

BSC

RNC

2G+3G SGSN (lu)

1. Inter system change decision

2. RARQ 3. ACRQ 3. ACRE 4. Security mode control (command) 4. Security mode control (complete) 5. RAAC 6. RACO 7. MPCR 8. SREQ 8. SACC 9. MPCA 10. RAB assignment (request) 11. RB setup request 11. RB setup complete 12. RAB assignment (response)

13. Packet data transfer

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1. The MS or the RAN decides to perform an inter system change which makes the MS switch to a new cell where Iu mode has to be used, and stops transmission to the network. 2. The MS initiates an RRC connection establishment and sends a Routing Area Update (RAU) Request (P-TMSI, Old RA, Old P-TMSI Signature, Update Type, CM) message to the combined 2G+3G-SGSN. Update Type shall indicate RA update or combined RA / LA update or combined RA / LA update with IMSI attach requested. A combined RA / LA update with IMSI attach requested occurs also if the MS has a follow on request, i.e. if there is pending uplink traffic (signalling or data). As an implementation option, the SGSN may use the follow-on request indication to release or keep the Iu connection after the completion of the RA update procedure. The SRNS shall add an identifier of the area where the message was received before passing the message to the 2G+3G-SGSN. The 2G+3G-SGSN stops transmission of N-PDUs to the MS. 3. Authentication/Ciphering functions may be executed. 4. Security functions may be executed. 5. The 2G+3G-SGSN validates the presence of the MS in the new RA. If due to roaming restrictions the MS is not allowed to be attached in the RA, or if subscription checking fails, the 2G+3G-SGSN rejects the RAU with an appropriate cause. If all checks are successful, the 2G+3G-SGSN updates MM and PDP contexts for the MS. A new P-TMSI may be allocated. A RAU Accept (P-TMSI, P-TMSI Signature) message is returned to the MS. For this inter system change, the 2G+3-SGSN derives the corresponding PDCP sequence numbers from the N-PDU sequence numbers stored in the SGSN PDP contexts by adding eight most significant bits “1”. These PDCP sequence numbers are stored in the SGSN PDP contexts. 6. The MS acknowledges the new P-TMSI by returning a RAU Complete message to the SGSN. 7. A Modify PDP context request N -> MS is sent from 2G+3G-SGSN to the MS. 8. If the MS has pending uplink data or signalling, it shall send a Service Request (P-TMSI, RAI, CKSN, Service Type) message to the SGSN. Service Type specifies the requested service. Service Type shall indicate one of the following: Data or Signalling. 9. The MS/UE responds with a Modify PDP context accept to the 2G+3G-SGSN MS -> N. 10. - 12. The 2G+3G-SGSN requests the SRNS to establish a radio access bearer by sending an RAB Assignment Request (RAB ID(s), QoS Profile(s), GTP-SNDs, GTPSNUs, PDCP-SNUs) message to the SRNS. The PDCP sequence numbers are derived from the N-PDU sequence numbers and stored in the PDP contexts in step 5. The SRNS sends a Radio Bearer Setup Request (PCDP-SNUs) message to the MS. The MS responds with a Radio Bearer Setup Complete (PDCP-SNDs) message. The SRNS responds with a RAB Assignment Response message. Note: The NSAPI value is carried in the RAB ID IE.

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1.2.17.2

Information System

Successful Inter System Cell Reselection Procedure (3G --> 2G) The inter system change from Iu mode to A/Gb mode takes place when an MS changes from UTRAN or GERAN Iu mode to A/Gb mode. Depending on the PMM state before the inter system change and whether the RA is changed or not, one of the following procedures is initiated by the MS: – When an MS in PMM-IDLE state changes to A/Gb mode without changing the RA, the MS shall follow the selective Routing Area Update (RAU) procedure. – When an MS in PMM-IDLE state changes to A/Gb mode and the RA changes, the MS shall initiate the GPRS RAU procedures. – When an MS in PMM-CONNECTED state changes to the A/Gb mode, the MS shall initiate the GPRS RAU procedure independent of whether the RA has changed or not. The RAU procedure is either combined RA / LA update or only RAU. A combined RA / LA update takes place in network operation mode I when the MS enters a new RA or when a GPRS-attached MS performs IMSI attach. The MS sends a RAU Request message indicating that an LA update may also need to be performed. In this case the SGSN forwards the LA update to the VLR. This concerns only idle mode (see 3GPP TS 23.122), as no combined RA / LA updates are performed during a CS connection. In the context of this specification, the terms RNS (or RNC) refer also to a GERAN BSS (or BSC) when serving an MS in Iu mode.

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Information System


MS/ UE

BSC

RNC

2G+3G SGSN (Gb) (lu)

1. Inter system change decision

2. RARQ 3. SRNS context request 3. SRNS context response 5. ACRQ 5. ACRE 6. SRNS Data forward command 7. Forward packets 8. Iu Release command 8. Iu Release complete 9. RAAC 10. RACO 11. MPCR 11. MPCA

12. Packet data transfer

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1. The MS or the RAN decides to perform an inter system change which makes the MS switch to a new cell where A/Gb mode has to be used, and stops transmission to the network. 2. The MS sends a RAU Request (old RAI, old P-TMSI Signature, Update Type) message to the 2G+3G-SGSN. Update Type shall indicate RAU or combined RA / LA update or combined RA / LA update with IMSI attach requested. A combined RA / LA update with IMSI attach requested occurs if the MS wants to perform an IMSI attach. The BSS shall add the Cell Global Identity including the RAC and LAC of the cell where the message was received before passing the message to the 2G+3GSGSN. 3. If the MS is PMM-CONNECTED state, the 2G+3G-SGSN sends an SRNS Context Request (IMSI) message to the SRNS. 4. Upon reception of the SRNS Context Request message, the SRNS starts buffering and stops sending downlink PDUs to the MS. The SRNS responds with an SRNS Context Response (GTP-SNDs, GTP-SNUs, PDCP-SNDs, PDCP-SNUs) message. The GTP sequence numbers are included for each PDP context indicating the next in-sequence downlink GTP-PDU to be sent to the MS and the next in-sequence GTP PDU to be tunnelled to the GGSN. For each active PDP context which uses lossless PDCP, the SRNS also includes the uplink PDCP sequence number (PDCP-SNU) and the downlink PDCP sequence number (PDCP-SND). PDCP-SNU is the PDCP sequence number for the next expected in-sequence uplink packet to be received from the MS. PDCP-SND is the PDCP sequence number of the first downlink packet for which successful transmission has not been confirmed. The 2G+3G-SGSN shall take off the eight most significant bits of the passed PDCP sequence numbers, thus converting them to SNDCP N-PDU numbers of the respective 2G GPRS PDP contexts. 5. Authentication/Ciphering functions may be executed. 6. If the MS is PMM-CONNTECTED, the 2G+3G-SGSN sends an SRNS Data Forward Command (RAB ID, Transport Layer Address, Iu Transport Association) message to the SRNS. This message informs the SRNS that the 2G+3G-SGSN is ready to receive data packets. Upon reception of SRNS Data Forward Command message from the 2G+3G-SGSN, the SRNS shall start the data-forwarding timer. 7. For each RAB indicated by the SRNS Data Forward Command, the SRNS starts duplicating and tunnelling the buffered GTP-PDUs back to the 2G+3G-SGSN. For each radio bearer which uses lossless PDCP, the GTP-PDUs related to transmitted but not yet acknowledged PDCP-PDUs are duplicated and tunnelled back to the 2G+3G-SGSN. Their related downlink PDCP sequence numbers are sent with them. The 2G+3G-SGSN converts the PDCP sequence numbers to SNDCP sequence numbers by taking off the eight most significant bits of the PDCP sequence numbers. 8. The 2G+3G-SGSN sends an Iu Release Command message to the SRNS. When the RNC data-forwarding timer has expired, the SRNS responds with an Iu Release Complete message. 9. The 2G+3G-SGSN validates the presence of the MS in the new RA. If due to roaming restrictions the MS is not allowed to be attached in the RA, or if subscription checking fails, the 2G+3G-SGSN rejects the RAU with an appropriate cause. If all checks are successful, the 2G+3G-SGSN updates MM and PDP contexts for the MS. A new P-TMSI may be allocated. A logical link is established between the new 2G+3G-SGSN and the MS. 2G+3G-SGSN initiates the establishment procedure. A RAU Accept (P-TMSI, P-TMSI Signature, Receive N-PDU Number) message is returned to the MS. The Receive N-PDU Number is equal to the converted PDCP-

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SNU. It contains the acknowledgements for each NSAPI which used lossless PDCP before the start of the update procedure. All mobile-originated N-PDUs which were successfully transferred before the start of the update procedure are thereby confirmed. If the Receive N-PDU Number confirms the reception of N-PDUs, these NPDUs shall be discarded by the MS. 10. The MS acknowledges the new P-TMSI by returning a RAU Complete (Receive NPDU Number) message to the SGSN. The Receive N-PDU Number is equal to the converted PDCP-SND. It contains the acknowledgements for each NSAPI which used lossless PDCP before the start of the update procedure. All mobile-terminated N-PDUs which were successfully transferred before the start of the update procedure are thereby confirmed. If the Receive N-PDU Number confirms the reception of N-PDUs, these N-PDUs shall be discarded by the 2G+3G-SGSN. The MS deducts Receive N-PDU Number from PDCP-SND by taking off the eight most significant bits. PDCP-SND is the PDCP sequence number for the next expected insequence downlink packet which is received in the MS per radio bearer and which used lossless PDCP. The new 2G-SGSN negotiates the use of acknowledged or unacknowledged SNDCP with the MS for each NSAPI, regardless whether the SRNS used lossless PDCP or not. 11. A Modify PDP context request N -> MS is sent from 2G+3G-SGSN to the MS. The MS responds with a Modify PDP context accept to the 2G+3G-SGSN MS -> N.

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1.2.18 1.2.18.1

MS

Information System

Other Procedures Idle Traffic Channel Supervision

BTS

BSC

MSC

RESIN (*) ILUPLKIC

MEITCHIB

.. .. .

.. .. . RESIN (*) ILUPLKIC

(*)

202

MEITCHIB

Contains the idle TCH measurements for all TCHs of the TRX currently not used for a call.

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1.2.18.2

Uplink and Downlink Measurement Reports on Abis

MS

BTS

BSC

MSC

MEAS REP MESRS (MEAS REP) (*) PWRUPDW CRXLVQUU CRXLVQUD CRXLVTAU CRXLVTAD CFERRXQU

.. .. .

.. .. .

.. .. .

.. .. .

MEAS REP MESRS (MEAS REP) (*) PWRUPDW CRXLVQUU CRXLVQUD CRXLVTAU CRXLVTAD CFERRXQU

(*)

Measurement Reports are transmitted for each TCH of the TRX currently seized by a call only if the feature ’Measurements on Abis’ (SET TRX: RADIOMR = TRUE) is enabled in the BSC database.

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1.2.18.3

Information System

IMSI Trace Invocation for Normal Call Setup

MS

BTS

BSC

MSC

Call setup ...

I (CMSREQ)

ESTIN (CMSREQ)

SDCCH

CR (CL3I; CMSREQ)

MRPCI CC (MSIT) STRAC DT1 (CICMD) ENCRY (CIMCMD)

I (CIMCMD) SDCCH

STRACACK I (CLAMCH)

DATIN (CLAMCH)

SDCCH

I (CIMCMP)

DATIN (CIMCMP)

SDCCH

DT1 (CLUPD) DT1 (CICMP) DT1 (TRCMD)

DATRQ (TRCMD) I (TRCMD) SDCCH

TMEASRES (MEASREP)

Call setup continuation and completion... TMEASRES (MEASREP) TMEASRES (MEASREP)


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1.2.18.4

MS

IMSI Trace Invocation for Incoming Inter-BSC Handover

BTSold

BSCold

MSC

BSCnew

BTSnew

CR (HO REQ) CHNAV (New TCH) CHNAK CC (HO RAC; HO CMD) DT1 (HO CMD; HO CMD) DT1 (MSIT) DATRQ (HO CMD) I (HO CMD) FACCH

Continuation of handover procedure ...

I (HO CMP) FACCH

DATIN (HO CMP) DT1 (HO CMP) MRPCI DT1 (CL CMD) (cause: handover successful)

RELRQ RELCN

DT1 (CL CMP)

STRAC STRACACK

RLSD RCHRL (Old TCH) RCHRA RLC TMEASRES (MEASREP) TMEASRES (MEASREP)


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1.3

Information System

GPRS Message Flows

1.3.1

GPRS Procedures This chapter describes the general procedures for GPRS Mobility Management and GPRS Session Management. The temporary block flows (TBF) which are used to transport signalling messages and user data between mobile and BSS are described in chapter 1.3.2.

1.3.1.1

GPRS Mobility Management: Attach Procedure BSC

MS

SGSN IMSI or P-TMSI, MS capability, multislot class

UL-TBF

ATRQ

DL-TBF

IDRQ

UL-TBF

IDRE

DL-TBF

ACRQ

UL-TBF

ACRE

4

DL-TBF

ATAC new P-TMSI

5

UL-TBF

ACOM

1 2

3

IMSI

The Attach procedure is used by the mobile to register for GPRS services. 1. 2.

3.

4. 5.

206

The mobile sends Attach Request containing information about its mobile capabilities, its mutual class and its IMSI or P-TMSI for identification. If the MS identifies itself with its P-TMSI but the P-TMSI is unknown in SGSN, the SGSN sends an Identity Request to the MS. The MS responds with Identity Response including its IMSI. In contrast to ciphering in existing GSM (between BTS and MS) GPRS ciphering is a function of the LLC layer in the SGSN and in the mobiles. If enabled in the SGSN it initiates the authentication and ciphering procedure. The network informs the MS that the Attach was accepted. The network may include a new P-TMSI in the Attach Accept message. If the Attach Accept contained a new P-TMSI, the MS confirms the reception with Attach Complete.

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1.3.1.2

GPRS Mobility Management: Detach Procedure

(Mobile initiated) MS

SGSN

BSC

1 2

UL-TBF

DTRQ detach type

DL-TBF

DTAC

The detach procedure is used by the mobile to deregister from GPRS services. 1. 2.

The mobile initiated detach might be triggered by user command from mobile menu or when the mobile is switched off. If the detach Type indicates that the detach is not due to power switch off, the SGSN sends a Detach Accept to the MS.

(Network initiated) MS

SGSN

BSC

1 2

DL-TBF

DTRQ detach type, cause

UL-TBF

DTAC

The network may initiate the GPRS detach when GPRS services are no longer accepted for a subscriber (e.g. the subscriber is cancelled from the HLR database). 1. 2.

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1.3.1.3

Information System

GPRS Session Management: Activate PDP Context MS

1 2

3

BSC

SGSN

UL-TBF

APCR

QoS, opt. PDP-address

DL-TBF

APAC

QoS, opt. dyn. PDP-address

UL-TBF

XID

DL-TBF

XID

A PDP context represents a logical connection between a mobile and the network with a specific PDP address for data routing (e.g. fixed or dynamic local IP address) and a specific Quality of Service profile (QoS). The Activate PDP Context procedure is used to establish the connection. If supported by the mobile several PDP Contexts with different QoS profiles might be active handling different applications. 1 In the Activate PDP Context Request the mobile includes a requested QoS. The MS . shall use the PDP Address Information Element to indicate whether it requires the use of a static PDP Address or whether it requires the use of a dynamic PDP address. The MS leaves the PDP Address IE empty to request a dynamic PDP address. 2 The network verifies if it can support the requested QoS and if it is allowed for this . subscriber. Depending on the result, the SGSN may accept the Activate PDP Context Request with the requested or another QoS, or the SGSN rejects the Activate PDP Context Request. If requested by the mobile, the SGSN assigns a dynamic PDP-address. The MS either accepts the negotiated QoS profile, or deactivates the PDP context. 3 In the XID messages, parameters of the LLC and SNDCP layer are negotiated be. tween the mobile and the SGSN.

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1.3.1.4

GPRS Session Management: Deactivate PDP Context (Mobile initiated) MS

BSC

SGSN

UL-TBF

DPRQ

DL-TBF

DPAC

cause

The deactivate PDP Context procedure is used to deactivate a specific PDP Context. E.g. the related dial up connection is disconnected. The mobile remains GPRS attached. Network initiated PDP Context Deactivation is done with reverse message directions.

1.3.1.5

GPRS: Paging

MS PAGING

1 2

SGSN

BSC P-TMSI or IMSI

PAPS

IMSI, Paging Area, opt. P-TMSI

UL-TBF

UI TLLI; CGI

DL-TBF

DTGR DL-Data

In GMM STANDBY status a mobile performs routing area updates but it doesn’t inform the network about cell changes. A MS in STANDBY state must be paged by the SGSN before a downlink transfer to that MS is possible. The Paging procedure is used by the network to determine the cell where the mobile is located and moves the GMM state to READY. 1. The SGSN includes the IMSI, information about the area in which the mobile shall be paged and if available a P-TMSI. If included, the BSC shall use the P-TMSI instead of IMSI in the PAGING message on the Um-interface. 2. In response to a GPRS page, the mobile usually sends an unnumbered Information frame (UI). However any other uplink data from the MS can be a valid paging response. The BSC adds the Cell Global Identity (CGI) including RAC and LAC of the cell where the message was received before passing the message to the SGSN.

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1.3.1.6

Information System

GPRS Mobility Management: Routing Area Update

MS

old BTS

UL/DL-TBFs (Data)

1

new BTS

BSC

SGSN

DTGR UL/DL-Data

UL-TBF

RARQ new CGI, old RAI

TLLI, old BVCI, opt.

FLUSH new BVCI

2

3

DL-TBF

FLUSH-ACK TLLI

2

UL-TBF 4

5

RAAC RAI; opt. new P-TMSI

UL/DL-TBFs (Data)

RACO

DTGR UL/DL-Data

A routing area update takes place when a GPRS attached MS detects that it has entered a new RA, when the periodic RA update timer has expired, or when a suspended MS is not resumed by the BSS. 1. In the new cell the mobile sends a Routing Area Update Request including the old Routing Area Identification and the reason for the routing area update. The BSC adds the new Cell Global Identity including RAC and LAC of the cell where the message was received before passing the message to the SGSN. 2. When the SGSN detects the routing area update, it sends a FLUSH-LL PDU to the old BVC to initiate the following procedure: - at a cell change between two NSEIs or between two routing areas, LLC-PDU(s) stored at the "old" BVCI for the TLLI are deleted. - in response to a FLUSH-LL PDU the BSS shall send a FLUSH-LL-ACK PDU to the SGSN containing: -the TLLI received in the FLUSH-LL PDU.

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3. The SGSN validates the presence of the MS in the new RA. If the MS is not allowed to be attached in the RA due to regional subscription restrictions, or if subscription checking fails, then the SGSN rejects the routing area update with an appropriate cause. If all checks are successful, then the SGSN updates the GMM context for the MS. A new P-TMSI may be allocated. A Routing Area Update Accept (RAAC) is returned to the MS. 4. The MS acknowledges the new P-TMSI by returning a Routing Area Update Complete (RACO). 5. Data transfer is continued in the new routing area.

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1.3.1.7

Information System

GPRS Mobility Management: Cell Update

MS

old BTS

UL/DL-TBFs (Data)

1

UL-TBF (UI)

new BTS

SGSN

BSC

DTGR UL/DL-Data

UI TLLI, new BVCI

TLLI, old BVCI, opt.

FLUSH new BVCI

2

FLUSH-ACK TLLI

3

4

UL/DL-TBFs (Data)

DTGR UL/DL-Data

1. A cell update takes place when the MS enters a new cell inside the current RA and the MS is in READY state. The MS performs the cell update procedure by sending an uplink LLC frame of any type containing the MS identity to the SGSN. Towards the SGSN, the BSS adds the BVCI and Cell Global Identity including RAC and LAC. 2. When the SGSN detects the cell change, it sends a FLUSH-LL PDU to the old BVC to initiate the following procedure: - at a cell change within one NSEI (e.g. one PCU represents one NSEI) and within one routing area, LLC-PDU(s) for a given TLLI stored at an "old" BVCI (corresponding to the old cell) are either deleted or transferred to a "new" BVCI (corresponding to the new cell) with which the TLLI is currently associated. 3. In response to a FLUSH-LL PDU the BSS shall send a FLUSH-LL-ACK PDU to the SGSN containing: - the TLLI received in the FLUSH-LL PDU and - an indication of whether the LLC-PDU(s) were "transferred" or "deleted". In case the SDUs were "transferred" the BVCI (new) IE shall be included. 4. Data transfer is continued in the new cell.

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1.3.1.8

GPRS: Suspend / Resume

MS

SGSN

BSS

UL/DL-TBFs (Data)

1

DTGR

UL/DL-Data

DTGR

DL-Data

Circuit switched traffic, e.g. Mobile Originated Call, answer to paging, Location Update 2

CHNREQ RACH DL-TBF

3

GPRSSU TLLI Cause

4 SDCCH

SUS TLLI SUSA RSTA TLLI

3

LLCD TLLI

DISC 5

CHNREL (Resume)

RES RESA

6

UL/DL-TBF

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UL/DL-Data

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Information System

The Suspend / Resume procedure is used to interrupt GPRS data traffic temporarily to allow circuit switched services, e.g. answer to Paging for an incoming call, a periodic Location Update or in our example a Mobile Originating Call. 1. The mobile is transferring data. 2. The mobile leaves the Packet data traffic channels and switches to the BCCH. It requests a signalling channel (SDCCH) by sending CHNREQ on the Random Access Channel. 3. If a downlink TBF is active during this time, it will fail because the mobile is no longer monitoring the PDTCHs. The BSC reports this lost downlink TBF with a Radio Status (RSTA) and the number of not transferred with a LLC-discarded (LLCD) towards the SGSN. 4. The mobile sends a GPRS Suspend Request on the SDCCH. The BSC forwards the Suspend to the SGSN. The call set-up continues. 5. The call ends and the circuit switched resources are released. The BSC includes the resume command towards the mobile in the channel release message and sends in parallel a resume message towards SGSN. 6. Whether data transfer is continued or not depends on the recovery mechanism and time out of the suspended application.

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1.3.2

LC/MAC Message Flows All afore mentioned GPRS Mobility Management and Data Transfer procedures use the RLC/MAC message flows described below. Data and GMM messages are transferred in Temporary Block Flows (TBF). Each TBF consists of the resource allocation, the transfer of RLC/MAC data blocks itself, the respective acknowledgements if required and the release of the resources. Four basic TBF types exist: – – – –

Uplink TBF Downlink TBF Concurrent Uplink TBF Concurrent Downlink TBF

This document decribes the RLC/MAC implementation of the BSS releases BR55/10 to BR55/14. As GPRS is constantly improved, slight changes will apply for the loads from BR55/15 onwards. PBCCH issues are not yet included in the message flows. This is the PBCCH feature is not officially released within BR55 and only a single type of phone is available for testing. In case more detailed information is required, please refer to the GSM specifications (RLC/MAC: GSM 04.60). Timeslot allocation of various multislot classes: Up- and downlink resources are allocated to the mobiles depending on their multislot classes. Multislot Class

# of TS

1 2 4 8

1+1 2+1 3 +1 4+1

Relative Timeslot Allocation DL: 1 - UL: 1 DL: 1,2 - UL: 2 DL: 1,2,3 - UL: 2 DL: 1,2,3,4 - UL: 3

This is important to understand the resource allocation for different mobiles on the RLC/MAC layer.

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1.3.2.1

Information System

Uplink TBF

MS

BSC

BTS

UL-LLC-Data in MS

CHNREQ (Uplink TBF)

1

CHNRD (Uplink TBF)

RACH

CHNAV PDCH

2

CHNAK

IACMD (IMASS) Packet UL Ass.: TFI; USF; CS

I (IMASS) Packet UL Ass.: TFI; USF; CS

3

AGCH

PCU-DL (PDDCB) USF

RMAC-DL (PDDCB) USF 4

5

PDTCH

(...) RMAC-UL (PUDCB) PDTCH

RMAC-UL (DATA) TLLI; BSN=0; CV=15

6 PDTCH

(...)

(...)

PCU-UL (PUDCB)

PCU-UL (DATA) TLLI; BSN=0; CV015 (...)

RMAC-UL (DATA) TLLI; BSN=x; CV=15

PCU-UL (DATA) TLLI; BSN=x; CV=15

PDTCH

RMAC-DL

7

TLLI;Contention Resolut.; (PUAN) Ack BSN=0; USF PACCH

RMAC-UL (DATA) TLLI; BSN=x+1; CV=15 PDTCH

(...)

216

PCU-DL (PUAN)

TLLI;Contention Resolution; Ack BSN=0; USF

PCU-UL (DATA) TLLI; BSN=0; CV=15 (...)

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MS

BTS

RMAC-UL (DATA) BSN=y; CV=15

PCU-UL (DATA) BSN=y; CV=15

PDTCH

8

RMAC-DL (PUAN)

Ack for NRLCMAX; USF PACCH

RMAC-UL (DATA)

BSN=y+1; CV=15

PDTCH

(...)

RMAC-UL (DATA)

BSN=z; CV=15

RMAC -UL (DATA) BSN=z+1; CV=14 PDTCH

Ack for BSN=NRLCMAX; USF

PCU-UL (DATA)

BSN=y+1; CV=15

PCU-UL (DATA)

BSN=z; CV=15

PCU-UL (DATA)

BSN=z+1; CV=14

(...)

(...)

10

PCU-UL (PUAN)

(...)

PDTCH

9

BSC

RMAC-UL (DATA) BSN=z+15; CV=0

PCU-UL (DATA) BSN=z+15; CV=0

PDTCH

RMAC-UL (PUDCB)

PCU-UL (PUDCB)

PDTCH

RMAC-UL (DATA) UL Data Repetition

PCU-UL (DATA)

PDTCH

(...)

UL Data Repetition

(...) Final Ack for BSN=z+15;

RMAC-DL

11 12

(PUAN) Ack BSN=z+15; RRBP=1

PCU-DL (PUAN) RRBP=1

PACCH

4 ACCESS BURST (PCA) PACCH

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Information System

Uplink TBF / One Phase Access on CCCH The purpose of the packet access procedure is to establish an uplink TBF to transfer LLC PDUs in the direction from the mobile station to the network. The scenario describes the packet access procedure on CCCH (no PBCCH is configured in the cell). With the one phase access, only a single PDCH can be allocated in the uplink direction, otherwise a two phase access is required. 1. The MS sends a Channel Request message with the establishment cause. For One phase packet access with request for single timeslot uplink transmission; one PDCH is needed (011110xx, 01111x0x, 01111xx0). 2. If no PDCH has been activated, a single timeslot will be configured as PDCH and the Time Alignment procedure is performed. 3. The BSC sends an Immediate Assignment towards the MS. A set of GPRS related parameters is included indicating e.g. the Temporary Flow Identifier (TFI), the Uplink State Flag (USF) and the Coding Scheme (CS). 4. Packet Downlink Dummy Control Blocks (PDDCB) with the USF value previously assigned to the MS are transmitted in the allocated PDCH. The MS monitors the USF of all downlink blocks on this timeslot to send its uplink data blocks as response to the occurence of its assigned USF. The PDDCBs continue during the whole uplink TBF - only the first one is drawn in the message flow! 5. A Mobile might send a Packet Uplink Dummy Control Block (PUDCB) as first block of an uplink TBF. This is probably because the uplink user data is not yet ready for transmission inside the MS. 6. The MS starts to send user data (LLC-frames) inside the uplink RLC/MAC blocks. The TLLI of the MS is included until the Contention Resolution procedure is completed (first PUAN with TLLI). The data blocks are counted up with the Block Sequence Number BSN (modulo 128). The Countdown Value CV remains at its maximum value as long as more than 15 RLC/MAC data blocks remain to be send. 7. The BSC acknowledges the first received uplink data block with a Packet Uplink Ack/Nack message (PUAN). As soon as the MS receives this first PUAN message including its TLLI, the Contention Resolution is completed and the MS continues sending its uplink data blocks without its TLLI inserted. The MS is now clearly identified - concurrent TBF handling according to its multislot capabilities is possible. 8. The BSC acknowledges every single uplink data block received from the mobile with a moving window mechanism. For this purpose the BSC sends every N-th block (N=NRLCMAX; BSS database parameter) a PUAN message indicating which blocks were correctly received or not. Missing blocks will be repeated by the mobile and acknowledged in the next scheduled PUAN message. 9. If the MS has sent most of its uplink data, the Countdown Value CV starts counting down towards the final block. This allows the network to calculate the remaining blocks of the running uplink TBF. 10. As soon as CV=0 is reached, the MS has transferred all uplink data. The uplink TBF however remains open until the last sent blocks were acknowledged by the BSS. The MS repeats uplink blocks that have been sent already before the final PUAN is received. 11. The BSC confirms the remaining uplink blocks with the final PUAN – the Final Ack Indication is set. Additionally the MS is polled with the RRBP-bit set to confirm the reception of this final PUAN.

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12. The Packet Control Ack (PCA) confirms the reception of the previous final PUAN. Now the uplink TBF is complete and the MS returns to monitor the BCCH.

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1.3.2.2

Information System

Downlink TBF

MS

BTS

BSC DL-LLC-Data on Gb

1

CHNAV (PDCH: TS 1,2,3 if necessary) CHNAK

2

3

4 5

6 7

I (IMASS)

IACMD (IMASS) Packet DL Ass.; TLLI; TFI; TS=2

Packet DL Ass.; TLLI; TFI; TS2 AGCH/PCH

RMAC-DL (PDAS) TLLI; TFI; RRBP=1;TS2

PCU-DL (PDAS) TLLI; TFI; RRBP=1send on TS2

PACCH

4 ACCESS BURST (PCA)

TS2

PCU-UL (PCA)

PACCH

TS2

PCU-DL (DATA) TFI; BSN=0; TS 1

RMAC-DL (DATA) TFI; BSN=0; TS 1 PDTCH

PCU-DL (PPCTA) TFI; TA value; TS2

RMAC-DL (PPCTA) TFI; TA value; TS2 PACCH

PCU-DL (DATA) TFI; BSN=1; TS3

RMAC-DL (DATA) TFI; BSN=1; TS3 PDTCH



(...)

8

RMAC-DL (DATA) TFI; BSN=19; TS2; RRBP=1

PCU-DL (DATA) TFI; BSN=19; TS2; RRBP=1

PDTCH



(...)

9

(...)

RMAC-UL (PDAN) TFI;Ack/Nack Description;TS2 PACCH

(...)

PCU-UL (PDAN) TFI;Ack/Nack Description;TS2

PCU-DL (DATA) TFI; BSN=y

RMAC-DL (DATA) TFI; BSN=y PDTCH

(...)

220

(...)

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MS

BTS

RMAC-DL (DATA)

BSC

PCU-DL (DATA) TFI; BSN=z-1

TFI; BSN=z-1

PDTCH

10

11

RMAC-DL (DATA)

TFI; BSN=z; TS2;

TFI; BSN=z; TS2; FBI=1; RRBP=1

PCU-DL (DATA) FBI=1; RRBP=1 PACCH

RMAC-UL (PDAN) PACCH

TFI; Final/ACK/NACK; TS2

PCU-UL (PDAN) TFI; Final/ACK/NACK; TS2

Downlink TBF / Example with a 3+1 Mobile / CCCH only A downlink TBF is initiated by the network as soon as LLC data coming from the GSN must be transferred towards the mobile. This scenario assumes the MS is in GMM ready state, therefore no paging is required or it was already performed including the paging response. 1. Downlink data (LLC-frame) arrives on the Gb-interface from the SGSN. 2. If no PDCH has been activated, the required number of timeslots will be configured as PDCH. The actually activated number of timeslots basically depends on the MS capabilities (which are known to the BSC since its GPRS attach), however less timeslots are possible under various circumstances (e.g. traffic load). For each timeslot a separate CHNAV/CHNAK message is required - the timeslot numbers indicated in the message flow are regarded as relative numbers! 3. The BSC sends an Immediate Assignment for a downlink TBF towards the MS. A set of GPRS related parameters is included, indicating e.g. the Temporary Logical Link Identity (TLLI) of the MS and the Temporary Flow Identifier (TFI) of the TBF. The IA message is either sent on the AGCH or the PCH - depending if the MS is still in Non-DRX Mode or not. Only a single timeslot can be allocated with the Immediate Assignment message. 4. The MS moves to the allocated PDCH timeslot (according the IA) where it receives the Packet Downlink Assignment (PDAS). This message now allocates all intended downlink timeslots (in our case three) and includes e.g. the TLLI as well as the TFI. Additionally the poll bit is set (RRBP=1) - the BSC requests a confirmation from the MS about the correct reception of the PDAS message. 5. The MS responds to the polling with a Packet Control Ack (PCA) - the PCA format is 4 access bursts. These access bursts are used by the BSC to calculate the initial timing advance value for the mobile.

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6. Downlink data transfer starts on timeslot 1. The MS listens on the assigned 3 timeslots to all downlink blocks with its own TFI, the RLC/MAC blocks are counted up with the Block Sequence Number (BSN). 7. The initial timing advance value is sent to the MS with a Packet Power Control/Timing Advance message (PPCTA). This allows the mobile to transmit (e.g. PDAN) before a continuous timing advance value is available. 8. Every N-th downlink data block (N=NRLCMAX, in this case the default value NRLCMAX=20 is used) the BSC polls the MS for a Packet Downlink Ack/Nack message (PDAN). This polling can only be sent on the timeslot of the TBF which is used for uplink signalling purpose - in case of a 3+1 MS timeslot #2 is used. 9. The MS answers the polling with a PDAN message. All RLC/MAC data blocks received by the MS until the transmission of this PDAN are acknowledged. A moving window mechanism is used. If blocks were not correctly received by the mobile, the BSC will repeat them soon after the reception of the PDAN. The repeated blocks will then be acknowledged in the next PDAN message. 10. If the end of the downlink transfer is reached (last BSN=z), the BSC sets the Final Block Indicator bit (FBI) in this last block and polls the MS for a final PDAN (RRBP=1). 11. The MS confirms the remaining downlink blocks with a PDAN. The Final Ack Indication is set, the downlink TBF is complete and no retransmissions are required. The MS remains on the PDCH and listens for new assignments until the timer T3192 expires. Afterwards it returns to listen to the BCCH.

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1.3.2.3

Concurrent UL TBF

MS

BTS

BSC PCU-DL (DATA) TFI; BSN

RMAC-DL (DATA) TFI; BSN PDTCH

UL-LLC-DATA in MS

PCU-DL (DATA) TFI; BSN


PCU-DL (PDAN) TFI; BSN

RMAC-DL (DATA) TFI; BSN

1

PDTCH

PCU-DL (DATA) TFI; BSN; TS2; RRBP=1


(...)

(...)

2

RMAC-UL (PDAN) TFI; Ch.Req.; TS2

PCU-UL (PDAN) TFI; Channel Request Des.; TS2

PACCH



(...)

PCU-DL (PUAS) TFI; USF; CS; TS2

RMAC-DL (PUAS) TFI; USF; CS

3

(...)

PACCH

PCU-DL (DATA) TFI; BSN; TS3


PCU-DL (PDDCB)

RMAC-DL (PDDCB) USF; TS2

4

USF; TS2

PDTCH

(...)

(...)


RMAC-DL (DATA) TFI; BSN; TS1 PDTCH

PCU-DL (DATA) TFI; BSN TS2; USF

RMAC-DL (DATA) TFI; BSN TS2; USF

5

PDTCH


RMAC-DL (DATA) TFI; BSN; TS3 PDTCH (...)

6

RMAC-UL (PUDCB) TLLI; TS2 PDTCH

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(...)

PCU-UL (PDDCB)

TLLI; TS2

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Information System

MS

7

BTS

RMAC-UL (DATA) BSN=0; CV=2; TS2

PCU-DL (DATA) BSN=0; CV=2; TS2

PDTCH

RMAC-UL (DATA) BSN=1; CV=1; TS2

PCU-DL (DATA) BSN=1; CV=1; TS2

PDTCH

8

BSC

RMAC-UL (DATA) BSN=2; CV=0; TS2 PDTCH

PCU-UL (DATA)

BSN=2; CV=0; TS2

PCU-UL (DATA)

UL Data Repetition; TS2

9

RMAC-UL (DATA) UL Data Repetition; TS2 PDTCH

(...)

(...) PCU-DL (DATA) TFI; BSN; TS1


10

PCU-DL (PUAN)

RMAC-DL (PUAN) Final Ack; RRBP=1; TS2

Final Ack; RRBP=1; TS2

PACCH



(...)

(...)

11

12


TS2

PCU-UL (PCA)

PACCH

TS2







(...)

(...)

All uplink transfer related messages / parameters are in blue colour and italics. The downlink TBF is ongoing similar to the DL-only description, however not all applicable blocks can be shown in this message flow.

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Concurrent UL TBF while a DL TBF is actice / Example with a 3+1 Mobile / CCCH only If a downlink TBF is already active and the MS needs to transmit data in uplink direction additionally, a concurrent uplink TBF is initiated. The described scenario occurs frequently for instance in case of a downlink FTP transfer: While the downlink data is transported in a continuously running DL TBF (in our example 3 timeslots), the FTP Acks need to be sent in uplink direction. Concurrent DL TBF while a UL TBF is active / Example with a 3+1 Mobile / CCCH only CAUTION: As the downlink transfer is continuously active during the whole uplink assignment (or even UL TBF), the usual DL message flow continues respectively. Please be aware that not all DL TBF related messages can be inserted in the message flow (please refer to DL TBF only description). 1. 2.

3.

4./5 6.

7.

8.

9. 10. 11. 12.

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LLC data is ready for uplink transmission towards the network. The downlink TBF is running. The MS requests resources for an uplink TBF within the next scheduled Packet Downlink Ack/Nack (PDAN) of the running downlink TBF. For this purpose it adds a Channel Request Description element inside the PDAN message. The BSC sends a Packet Uplink Assignment (PUAS) towards the MS. The Temporary Flow Identifier (TFI), the Uplink State Flag (USF) and the Coding Scheme (CS) are specified. The PUAS is sent on relative timeslot 2 which is used as uplink timeslot in case of a 3+1 MS. The BSC sets the assigned USF in downlink blocks on timeslot 2. The MS might send a Packet Uplink Dummy Control Block (PUDCB) as first block of the new UL TBF. This probably because the uplink user data is not yet ready for transmission inside the MS. The MS starts sending the uplink user data. The Contention Resolution procedure is not necessary as the MS is aIready clearly identified by the running DL TBF. In our example the complete uplink transfer consists of only 3 RLC/MAC blocks, which is a typical scenario for FTP uplink Acks in a downlink FTP. The last uplink block is sent with the Countdown Value (CV) = 0. This indicates the complete transmission of the uplink data and triggers the final Packet Uplink Ack/Nack (PUAN) message. The MS repeats the uplink blocks until the final PUAN has been received by the MS. The BSC sends the final Packet Uplink Ack/Nack (PUAN) and polls the MS to confirm its reception (RRBP=1). A Packet Control Ack (PCA) is sent by the MS as response to the previous polling. The downlink TBF continues solely.

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Information System

Concurrent DL TBF

BTS

MS

1

BSC PCU-DL (PDDCB) USF;TS2

RMAC-DL (PDDCB) USF;TS2 PDTCH

RMAC-UL (DATA) BSN; CV=15; TS2 PDTCH

RMAC-DL (PUAN) Ack BSN#; USF; TS2

PCU-UL (DATA)

BSN; CV=15

PCU-DL (PUAN)

Ack BSN#; USF; TS2

PACCH

RMAC-UL (DATA) BSN; CV=15; TS2

PCU-UL (DATA) BSN; CV=15; TS2

PDTCH

DL-LLC-Data on Gb

(...)

(...)

CHNAV PDCH; TS 1,3; please refer to text

2

CHNAK

3

(...)

4

PCU-DL (PDDCB)

RMAC-DL (PDDCB) USF; TS2 PDTCH

RMAC-UL (DATA) BSN; CV=15; TS2


PDTCH

5

USF; TS2

RMAC-DL (PDAS)

TLLI; TFI; RRBP=1; TS2 PACCH

PCU-DL (PDAS)

TLLI; TFI; RRBP=1; TS2

PCU-DL (PDDCB) USF; TS2

RMAC-DL (PDDCB) USF; TS2 PDTCH

RMAC-UL (DATA)

BSN; CV=15; TS2

PDTCH

(...) 6


(...) TS2

PACCH

RMAC-UL (DATA) BSN; CV=15; TS2 PDTCH

(...)

226


PCU-UL (PCA)

TS2

PCU-UL (DATA)

BSN; CV=15; TS2

(...)

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Information System


MS

7

BTS RMAC-DL (DATA) TFI; BSN=0; TS1

BSC PCU-DL (DATA)

TFI; BSN=0; TS1

PCU-DL (DATA)

TFI; BSN=1; TS2; USF

PDTCH

RMAC-DL (DATA) TFI; BSN=1; TS2; USF PDTCH

RMAC-UL (DATA) BSN; CV=15

PCU-UL (DATA) BSN; CV=15

PDTCH

PCU-DL (DATA)

RMAC-DL (DATA) TFI; BSN=2; TS3

TFI; BSN=2; TS3

PDTCH

(...)

(...)

RMAC-DL (DATA)

TFI; BSN=18; TS1

PCU-DL (DATA)

TFI; BSN=18; TS1

PCU-DL (DATA)

TFI; BSN=19; TS2; RRBP=1; USF

PCU-UL (DATA)

BSN; CV=15

PCU-DL (DATA)

TFI; BSN=20; TS3

PDTCH

8

RMAC-DL (DATA) TFI; BSN=19;... PDTCH

RMAC-UL (DATA) BSN; CV=15 PDTCH


(...)

(...)

9

RMAC-UL (PDAN) TFI; Ack/Nack Des.; TS2

PCU-UL (PDAN)

PACCH

(...)

(...) 10

RMAC-DL (DATA)

PCU-DL (DATA)

TFI; BSN=33;...

TFI; BSN=33; TS2; FBI=1; RRBP=1; USF

PDTCH

RMAC-UL (DATA) BSN; CV=15 PDTCH

(...)

PCU-UL (DATA) BSN; CV=15 (...)

RMAC-UL (PDAN) 11

TFI; Ack/Nack Des.; TS2

PACCH

(...)

TFI; Final Ack/Nack Des.; TS2

PCU-UL (PDAN)

TFI; Final Ack/Nack Des.; TS2

(...) All downlink transfer related messages / parameters are in blue colour and italics. The uplink TBF is ongoing similar to the UL-only description, however not all applicable blocks can be shown in this message flow.

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Concurrent DL TBF while a UL TBF is active / Example with a 3+1 Mobile / CCCH only If an uplink TBF is already running and the MS needs to send data in downlink direction additionally, a concurrent downlink TBF is initiated. The described scenario occurs frequently for instance in case of an uplink FTP transfer: While the uplink data is transported in a continuously running UL TBF (in our example 1 timeslot), the FTP ACKs need to be sent in downlink direction. CAUTION: As the uplink transfer is continuously active during the whole downlink assignment (or even DL TBF), the usual UL message flow continues respectively. Please be aware that not all UL TBF related messages can be inserted in the message flow (please refer to UL TBF only description). 1.

An uplink transfer between the MS and the BSS is ongoing. We assume the relative timeslot 2 is already used for the uplink transfer because an uplink FTP is already running for a longer time. In case the uplink TBF was just opened on the relative timeslot 1 and a first concurrent downlink TBF is required, the system will send a Packet Timeslot Reconfigure message (PTR) instead of the PDAS (see below). This because the position of the running uplink TBF must be moved to the relative timeslot 2 during a 3 timeslot downlink TBF. 2. Downlink data (LLC-frame) arrives on the Gb-interface from the GSN. 3. If only a single PDCH is activated yet, two more timeslots will be configured as PDCH and the Time Alignment procedure is performed on these new timeslots. 4. The uplink TBF continues - PDDCBs indicate the assigned USF towards the MS, the MS sends its data in the next uplink block. 5. The BSC sends a Packet Downlink Assignment (PDAS) towards the MS. This message assignes the used downlink TBF timeslots and the Temporary Flow Identifier (TFI) to the MS (TLLI). Additionally the poll bit is set (RRBP=1) - the BSC requests a confirmation from the MS about the correct reception of the PDAS message. 6. The MS responds to the polling with a Packet Control ACK (PCA) in the reserved uplink block. The uplink TBF is meanwhile ongoing. 7. The BSC starts sending the downlink data blocks of the new TBF. The DL data blocks on TS 2 continue setting the USF bit for the ongoing uplink TBF. 8. After NRLCMAX blocks are sent, the BSC polls the MS for a Packet Downlink ACK/NACK message (PDAN). (In our case NRLCMAX=20, therefore the downlink data block with BSN=19 polls the MS). Due to the polling this block must be sent on TS 2 even if a different NRLCMAX value suggests another timeslot. 9. The PDAN message from the MS is received in the reserved uplink radio block. All RLC/MAC data blocks successfully received by the MS until the transmission of this message are acknowledged. 10. The final downlink data block is sent from the BSC. The Final Block Indicator Bit (FBI) is set and the BSC polls for a final Packet Downlink ACK/NACK (RRBP=1). Due to the polling, also this block must be sent on TS 2 independent of the previous sequence. 11. The final PDAN confirms all remaining RLC/MAC blocks of the downlink TBF.

228

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2 Counter / Message Abbreviations Abbreviation

Long Name

Type

-AABORT ACRE ACRQ AGCH ALERT ASS CMD ASS CMP ASS COM ASS FAIL ASS FAI ASS REQ AUTREP AUTREQ

ABORT AUTHENTICATION & CIPHERING RESPONSE AUTHENTICATION & CIPHERING REQUEST ACCESS GRANT CHANNEL ALERTING ASSIGNMENT COMMAND ASSIGNMENT COMPLETE ASSIGNMENT COMPLETE ASSIGNMENT FAILURE ASSIGNMENT FAILURE ASSIGNMENT REQUEST AUTHENTICATION RESPONSE AUTHENTICATION REQUEST

BSSLAP Message GMM (GPRS MM/SM) Message GMM (GPRS MM/SM) Message Um Channel DTAP Message DTAP Message DTAP Message BSSMAP Message DTAP Message BSSMAP Message BSSMAP Message DTAP Message DTAP Message

BROADCAST CONROL CHANNEL BCCH INFORMATION INTERCELL HANDOVER CONDITION INDICATION BASE STATION MANAGEMENT APPLICATION PART

Um Channel Um Message Abis RSL Message

CONNECTION CONFIRM CALL CONFIRMED CHANNEL MODE MODIFY CHANNEL MODE MODIFY ACKNOWLEDGE CHANNEL ACTIVATION ACKNOWLEDGE CHANNEL ACTIVATION CHANNEL REQUIRED CHANNEL REQUEST CHANNEL RELEASE CIPHER MODE COMMAND CIPHER MODE COMPLETE CIPHERING MODE COMMAND CIPHERING MODE COMPLETE CLASSMARK CHANGE CLASSMARK CHANGE CLEAR COMMAND

SCCP Message DTAP Message DTAP Message DTAP Message Abis RSL Message Abis RSL Message Abis RSL Message Um Message DTAP Message BSSMAP Message BSSMAP Message DTAP Message DTAP Message DTAP Message Abis RSL Message BSSMAP Message

-BBCCH BCINF BWHCI BSSMAP

A-Protocol

-CCC CCONF CHMM CHMMACK CHNAK CHNAV CHNRD CHNREQ CHREL CICMD CICMP CIMCMD CIMCMP CLAMCH CLCH CL CMD

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Abbreviation CL CMP CLUPD CL REQ CL3I CMSACC CMSREQ COIN (BSC->SMLC) CONACK CONNECT CPACK CPDAT CPROC CR CREF

Long Name

Type

CLEAR COMPLETE CLASSMARK UPDATE CLEAR REQUEST COMPLETE LAYER 3 INFORMATION CM SERVICE ACCEPT CM SERVICE REQUEST CONNECTION ORIENTED INFORMATION CONNECT ACKNOWLEDGE CONNECT SHORT MESSAGE CP-ACK SHORT MESSAGE CP-DATA CALL PROCEEDING CONNECTION REQUEST CONNECTION REFUSED

BSSMAP Message BSSMAP Message BSSMAP Message BSSMAP Message DTAP Message DTAP Message BSSMAP-LE Message DTAP Message DTAP Message DTAP Message DTAP Message DTAP Message SCCP Message SCCP Message

DATIN DATRQ DELIN DESAC DISC DISC DM DTAP

DATA INDICATION DATA REQUEST DELETE INDICATION DEACTIVATE SACCH DISCONNECT DISCONNECT DISCONNECT MODE DIRECT TRANSFER APPLICATION PART

DT1

DATA FORM 1

Abis RSL Message Abis RSL Message Abis RSL Message Abis RSL Message DTAP Message Um layer 2 Message Um layer 2 Message Protocol (MS<->BSC, MS<->MSC) SCCP Message

EMERGENCY SETUP ENCRYPTION COMMAND ERROR INDICATION ESTABLISH CONFIRM ESTABLISH INDICATION ESTABLISH REQUEST TIMING ADVANCE REQUEST TIMING ADVANCE RESPONSE

DTAP Message Abis RSL Message Abis RSC Message Abis RSL Message Abis RSL Message Abis RSL Message BSSLAP Message BSSLAP Message

-D-

-EEMSETUP ENCRY ERIN ESTCN ESTIN ESTRQ E-TA_REQ (SMLC->BSC) E-TA_RES (BSC->SMLC)

230

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Abbreviation

Long Name

Type

-FFACCH FACIL FHREQ FR

FAST ASSOCIATED CONTROL CHANNEL FACILITY FORCED HO REQUEST FULL RATE

Um Channel DTAP Message Abis RSL Message Speech Version

HANDOVER DETECTION HANDOVER COMMAND HANDOVER COMPLETE HANDOVER DETECT HANDOVER FAILURE HANDOVER FAILURE HANDOVER PERFORMED HANDOVER REQUEST ACKNOWLEDGE HANDOVER REQUEST HANDOVER REQUIRED HANDOVER REQUIRED REJECT HALF RATE

Abis RSL Message DTAP Message DTAP Message BSSMAP Message DTAP Message BSSMAP Message BSSMAP Message BSSMAP Message BSSMAP Message BSSMAP Message BSSMAP Message Speech Version

INFORMATION IMMEDIATE ASSIGN COMMAND IMMEDIATE ASSIGNMENT IMMEDIATE ASSIGNMENT REJECT IMSI DETACH INDICATION IMMEDIATE SETUP MESSAGE INTER SYSTEM HANDOVER TO UTRAN

Um layer2 Message Abis RSL Message DTAP Message DTAP Message DTAP Message BSSMAP Message DTAP-RR Message

-G-

-HHANDO HO CMD HO CMP HO DET HO FAIL HO FAI HO PER HO RAC HO REQ HO RQD HO RRJ HR -II IACMD IMASS IMASSRJ IMDETIN IMSETUP ISHUTRAN -J-

-K-

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Information System

Abbreviation

Long Name

Type

-LLCSREQ (BSC->BTS) LCSRRES (BTS->BSC) LUACC LUREQ

LOCATION BASED SERVICES REQUEST LOCATION BASED SERVICES RESPONSE LOCATION UPDATING ACCEPT LOCATION UPDATING REQUEST

DTAP Message DTAP Message

MEASUREMENT REPORT MEASUREMENT RESULT MODE MODIFY ACKNOWLEDGE MODE MODIFY REQUEST MODIFY PDP CONTEXT ACCEPT MS -> N MODFY PCP CONTEXT REQUEST N -> MS MS RF POWER CAPABILITY INDICATION MSC INVOKE TRACE

Um Message Abis RSL Message Abis RSL Message Abis RSL Message GMM (GPRS MM/SM) Message GMM (GPRS MM/SM) Message Abis RSL Message BSSMAP Message

NOTIFICATION CHANNEL NOTIFICATION COMMAND

UM Channel SRSL

OVERLOAD

Abis RSL Message

PAGING PAGING REQUEST PAGING RESPONSE PREFERRED AREA PREFERRED AREA REQUEST PAGING CHANNEL PAGING COMMAND PHYSICAL CONTEXT CONFIRM PHYSICAL CONTEXT REQUEST PERFORM LOCATION REQUEST PERFORM LOCATION REQUEST PERFORM LOCATION RESPONSE PERFORM LOCATION RESPONSE PROGRESS

BSSMAP Message Um Message DTAP Message Abis RSL Message Abis RSL Message Um Channel Abis RSL Message Abis RSL Message Abis RSL Message BSSMAP Message BSSMAP-LE Message BSSMAP Message BSSMAP-LE Message DTAP Message

-MMEAS REP MESRS MOMAK MOMRQ MPCA MPCR MRPCI MSIT -NNCH NOTCMD -OOVERLOAD -PPAGIN PAGREQ PAGRES PAREA PAREQ PCH PGCMD PHCCN PHCRQ PLRQ (MSC->BSC) PLRQ (BSC->SMLC) PLRS (BSC->MSC) PLRS (SMLC->BSC) PROGRES

232

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Abbreviation

Long Name

Type

-QQUIND

QUEUING INDICATION

BSSMAP Message

ROUTING AREA UPDATE ACCEPT RANDOM ACCESS CHANNEL ROUTING AREA UPDATE COMPLETE ROUTING AREA UPDATE REQUEST RF CHANNEL RELEASE ACKNOWLEDGE RF CHANNEL RELEASE RELEASE COMPLETE RELEASE CONFIRM RELEASE RELEASED INDICATION RELEASE REQUEST RESET RF RESOURCE INDICATION RETRIEVE ACKNOWLEDGE RETRIEVE RELEASE COMPLETE RELEASED RP-ACK RP-DATA RADIO SIGNALLING LINK

GMM (GPRS MM/SM) Message Um Channel GMM (GPRS MM/SM) Message GMM (GPRS MM/SM) Message Abis RSL Message Abis RSL Message DTAP Message Abis RSL Message DTAP Message Abis RSL Message Abis RSL Message BSSLAP Message Abis RSL Message DTAP Message DTAP Message SCCP Message SCCP Message SMRP Message SMRP Message Abis-Protocol

SET ASYNCHRONOUS BALANCED MODE SERVICE ACCEPT SACCH FILLING SLOW ASSOCIATED CONTROL CHANNEL SERVICE ACCESS POINT IDENTIFIER SMS BROADCAST COMMAND SIGNALLING CONNECTION CONTROL PART STAND ALONE DEDICTED CONTROL CHANNEL SETUP STOP DTMF ACKNOWLEDGE STOP DTMF SERVICE REQUEST START DTMF ACKNOWLEDGE START DTMF START TRACE

Um layer2 Message GMM (GPRS MM/SM) Message Abis RSL Message Um Channel LAPD Addressing ID Abis RSL Message CCS7 User Part Um Channel DTAP Message DTAP Message DTAP Message GMM (GPRS MM/SM) Message DTAP Message DTAP Message Abis RSL Message

-RRAAC RACH RACO RARQ RCHRA RCHRL RELCMP RELCN RELEAS RELIN RELRQ RESET RESIN RETRACK RETRV RLC RLSD RPAC RPDA RSL -SSABM SACC SACFL SACCH SAPI SBCCM SCCP SDCCH SETUP SPDACK SPDTMF SREQ STDACK STDTMF STRAC

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Abbreviation STRACACK

Information System

Long Name

Type

START TRACE ACKNOWLEDGE

Abis RSL Message

TALKER DETECT MESSAGE TALKER INDICATION MESSAGE TIMING ADVANCE REQUEST TIMING ADVANCE RESPONSE TRAFFIC CHANNEL TRACE MEASUREMENT RESULTS TMSI REALLOCATION COMMAND TMSI REALLOCATION COMPLETE

DTAP Message DTAP Message BSSLAP Message BSSLAP Message Um Channel Abis RSL Message DTAP Message DTAP Message

UNNUMBERED ACKNOWLEDGEMENT UNIT DATA UNNUMBERED INFORMATION UPLINK REQUEST CONFIRM MESSAGE UPLINK ACCESS UPLINK GRANT MESSAGE UPLINK BUSY MESSAGE UPLINK FREE MESSAGE UPLINK RELEASE UPLINK REQUEST ACKNOWLEDGE UPLINK RELEASE COMMAND UPLINK RELEASE INDICATION UPLINK REQUEST MESSAGE UPLINK SEIZED COMMAND UTRAN CLASSMARK CHANGE

Um layer2 Message SCCP Message Um layer2 Message BSSMAP Message DTAP DTAP DTAP DTAP DTAP BSSMAP Message BSSMAP Message BSSMAP Message BSSMAP Message BSSMAP Message Abis RSL Message

VGCS ASSIGNMENT RESULT VGCS ASSIGNMENT REQUEST MESSAGE VGCS SETUP MESSAGE VGCS SETUP ACKNOWLEDGE

BSSMAP Message BSSMAP Message BSSMAP Message BSSMAP Message

INTRACELL HANDOVER CONDITION INDICATION

Abis RSL Message

-TTALKDET TALKIND TAREQ (SMLC->BSC) TARSP (BSC->SMLC) TCH TMEASRES TRCMD TRCMP -UUA UDT UI UPCF UPLACC UPLGRT UPLINKBUSY UPLINKFREE UPLREL UPRA UPRC UPRI UPRQ UPSC UTRANCC -VVVAR VVRQ VVS VVSA -WWIHCI

234

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3


Abbreviations

BSC

Base Station Controller

BSIC

Base Station Identity Code

BSSLAP

BSS LCS Assistance Protocol

BSSMAP

BSS Management Application Part

BSSMAP-LE BSSMAP LCS Extension BTS

Base Transceiver Station

CI

Cell Identifier

CITASUP

This BSC DB parameter represents the flag to enable the transmission of the Cell Identifier (CI) and Timing Advance (TA) to MSC.

emLPP

enhanced Multi-Level Procedure and Preemption

GPRS

General Packet Radio Services

LCSNSSC

This BSC DB enables LCS NSS centric solution. For LCS BSS centric solution it must be always set to FALSE.

MS

Mobile Station

MSC

Mobile-Services Switching Center

MT-LR

Mobile Terminating Location Request

NI-LR

Network Induced Location Request

SBS

Siemens Base Station System

SETPAR

SET PARAMETER

SIT10

Set Information Type 10

SMLC

Serving Mobile Location Center

SSI10

Set System Info 10

TA

Timing Advance

TERM

TERMINATION

TERMREQ

TERMINATION REQUEST

TMSI

Temporary Mobile Subscriber Identity

UDTRQ

Unit Data Request

URC

Uplink Request Confirm

URLC

Uplink Request CMD

USC

Uplink Seized Command

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236

Information System

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l3 Message 2g

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