IP RAN Description Issue 02 Date 2008-07-30 Huawei Proprietary and Confidential Copyright © Huawei Technologies Co

RAN

IP RAN Description

Issue

02

Date

2008-07-30

Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd

Huawei Technologies Co., Ltd. provides customers with comprehensive technical support and service. For any assistance, please contact our local office or company headquarters.

Huawei Technologies Co., Ltd. Address:

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Website:

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Email:

[email protected]

Copyright © Huawei Technologies Co., Ltd. 2008. All rights reserved. No part of this document may be reproduced or transmitted in any form or by any means without prior written consent of Huawei Technologies Co., Ltd.

Trademarks and Permissions and other Huawei trademarks are trademarks of Huawei Technologies Co., Ltd. All other trademarks and trade names mentioned in this document are the property of their respective holders.

Notice The information in this document is subject to change without notice. Every effort has been made in the preparation of this document to ensure accuracy of the contents, but all statements, information, and recommendations in this document do not constitute the warranty of any kind, express or implied.


RAN IP RAN Description

Contents

Contents 1 IP RAN Change History ...........................................................................................................1-1 2 IP RAN Introduction .................................................................................................................2-1 3 IP RAN Principles......................................................................................................................3-1 3.1 IP RAN Application Scenarios......................................................................................................................3-1 3.1.1 Iub over TDM Network .......................................................................................................................3-1 3.1.2 Iub over IP Network.............................................................................................................................3-2 3.1.3 Iub over Hybrid IP Transport Network ................................................................................................3-3 3.1.4 Iub over IP/ATM Network ...................................................................................................................3-4 3.1.5 Iu/Iur over IP Network .........................................................................................................................3-5 3.2 IP RAN Protocol Stacks ................................................................................................................................3-5 3.2.1 Protocol Stack of Iub (over IP) ............................................................................................................3-5 3.2.2 Protocol Stack of Hybrid Iub (over IP /TM) ......................................................................................3-10 3.2.3 Protocol Stack of Iu-CS (over IP) ......................................................................................................3-13 3.2.4 Protocol Stack of Iu-PS (over IP).......................................................................................................3-14 3.2.5 Protocol Stack of Iur (over IP) ...........................................................................................................3-15 3.2.6 Protocols of Data Link Layer.............................................................................................................3-16 3.3 IP Addresses and Routes of IP RAN ...........................................................................................................3-17 3.3.1 Two Networking Types on the Iub/Iur/Iu-CS/Iu-PS Interfaces ..........................................................3-17 3.3.2 Route on the Iub/Iur/Iu-CS/Iu-PS Interface .......................................................................................3-19 3.3.3 IP Addresses for SCTP Links and IP Paths Between RNC and NodeB .............................................3-19 3.4 IP RAN QoS................................................................................................................................................3-20 3.4.1 Admission Control and Congestion Control ......................................................................................3-21 3.4.2 Differentiated Service ........................................................................................................................3-21 3.4.3 PQ and RL .........................................................................................................................................3-21 3.5 IP RAN VLAN............................................................................................................................................3-22 3.5.1 Ensuring Security...............................................................................................................................3-22 3.5.2 Providing Priority Service..................................................................................................................3-23 3.6 IP RAN FP-Mux..........................................................................................................................................3-24 3.7 IP RAN Header Compression .....................................................................................................................3-25 3.7.1 ACFC .................................................................................................................................................3-25 3.7.2 PFC ....................................................................................................................................................3-25 3.7.3 IPHC ..................................................................................................................................................3-25

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Contents

3.8 IP RAN Redundancy ...................................................................................................................................3-26 3.8.1 Single-Homing Layer 3 Networking..................................................................................................3-26 3.8.2 Dual-Homing Layer 3 Networking ....................................................................................................3-26 3.8.3 Advantages and Disadvantages of the Networking............................................................................3-27 3.8.4 Configuration on the RNC Side .........................................................................................................3-27 3.8.5 Fault Detection...................................................................................................................................3-28 3.9 IP RAN Load Sharing .................................................................................................................................3-28 3.9.1 Load Sharing Layer 3 Networking.....................................................................................................3-28 3.9.2 Advantage and Disadvantage of the Networking ...............................................................................3-29 3.9.3 Configuration on the RNC Side .........................................................................................................3-29 3.10 IP RAN DHCP ..........................................................................................................................................3-29 3.11 IP RAN Transport Capabilities..................................................................................................................3-30 3.11.1 RNC IP Transport Capabilities.........................................................................................................3-30 3.11.2 BBU IP Transport Capabilities.........................................................................................................3-31 3.11.3 Macro NodeB IP Transport Capabilities ..........................................................................................3-32

4 IP RAN Parameters ....................................................................................................................4-1 5 IP RAN Reference Documents ................................................................................................5-1

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1 IP RAN Change History

1

IP RAN Change History

IP RAN Change History provides information on the changes between different document versions.

Document and Product Versions Document Version

RAN Version

RNC Version

NodeB Version

02 (2008-07-30)

10.0

V200R010C01B061

V100R010C01B050 V200R010C01B041

01 (2008-05-30)

10.0

V200R010C01B051

V100R010C01B049 V200R010C01B040

Draft (2008-03-20)

10.0

V200R010C01B050

V100R010C01B045

There are two types of changes, which are defined as follows: z

Feature change: refers to the change in the IP RAN feature of a specific product version.

z

Editorial change: refers to the change in information that was already included or the addition of information that was not described in the previous version.

02 (2008-07-30) This is the document for the second commercial release of RAN10.0. Compared with 01 (2008-05-30) of RAN10.0, issue 02 (2008-07-30) of RAN10.0 incorporates the changes described in the following table. Change Type

Change Description

Parameter Change

Feature change

More information about NodeB Iub interface boards is added. For details, see chapter 2 "IP RAN Introduction", and section 3.1 "IP RAN Application Scenarios".

None.

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Change Type

Change Description

Parameter Change

The description of IP addresses for SCTP links and IP paths for NodeB V200R010 is added to section 3.3 IP Addresses and Routes of IP RAN.

None.

None.

The parameters modified are listed as follows:

None.

Editorial change

z

Signalling link model is modified to Signalling link mode.

z

IU trans bearer type is modified to IU transfers bearer type.

z

Next hop IP address is modified to Forward route address.

z

IP Address is modified to NodeB IP_TRANS IP address and NodeB ATM_TRANS IP address.

z

IP Head compress is modified to IP Header Compress.

z

MCPPP is modified to Multi Class PPP.

z

Bear Type(ADD IUBCP) is modified to NCP/CCP Bearing Type.

The parameters added are listed as follows: z

IUB trans bearer type

z

IP Trans Apart Ind

z

Backup port IP address

z

Backup port mask

z

Backup port gateway IP address

z

Signal Priority

A parameter list is added. See chapter 4 IP RAN Parameters.

None.

None.

None.

01 (2008-05-30) This is the document for the first commercial release of RAN10.0. Compared with draft (2008-03-20) of RAN10.0, issue 01 (2008-05-30) of RAN10.0 incorporates the changes described in the following table.

1-2


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Change Type

Change Description

Parameter Change

Feature change

IP transport capabilities of DBS3900 and iDBS3900 are added to 3.11 IP RAN Transport Capabilities.

None.

Information of NodeB V200R010C01B040 is added to 2 IP RAN Introduction.

None.

The parameter is changed in 3.8 IP RAN Redundancy.

The renamed parameters are listed as follows: Times of out-time of BFD packet is modified to detect multiplier of BFD packet.

The parameter is changed in 3.6 IP RAN FP-Mux.

The changed parameter is listed as follows: Mux package number is changed to Maximum Frame Length.

None.

Editorial change

Issue 02 (2008-07-30)

General documentation change: z

The IP RAN Parameters is removed because of the creation of RAN10.0 parameter reference.

z

The structure is optimized.

The parameters that are changed to be non-configurable are listed as follows: z


z

IP Trans Apart Ind

z

IUR trans bearer type

z

Address and control field compress

z

Address & Control Field Compress

z

Protocol field compress (NodeB)

z

Protocol field compress (RNC)

z

VLAN Tag (NodeB)

z

Signaling priority (NodeB)

z


z

Backup port mask

z


z

ARP packet out-time

z

ARP packet resend times

None.


1-3



Draft (2008-03-20) This is a draft of the document for the first commercial release of RAN10.0. Compared with issue 03 (2008-01-20) of RAN 6.1, this issue incorporates the changes described in the following table. Change Type

Change Description

Parameter Change

Feature change

The port backup mode is changed in 1.3.8 IP RAN Redundancy.

The following parameters are deleted: z

Slot 14 interface board type

14 interface board Backup type The following parameters are added:

z

The fault detection is added in 1.3.8 IP RAN Redundancy.

z

Board type

z

Backup

z

Port No.

The following parameters are added: z

Check type

z

Port work mode

z

Min interval of BFD packet send [ms]

z

Min interval of BFD packet receive [ms]

z

Times of out-time of BFD packet

z

ARP packet out-time

z

ARP packet resend times

The IP interface boards POUa and UOIa are added in 1.2.1 IP RAN Introduction.

None

IP RAN FP-Mux is added in 1.3.6 IP RAN FP-Mux.

The following parameters are added:

The configuration on the RNC side is changed in 1.3.9 IP RAN Load Sharing.

z

FPMUX flag

z

Max subframe length

z

Mux package length

z

FPTIME

The following parameter is deleted:

14 interface board Backup type The following parameter is added:

z

z

1-4

Backup


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Change Type

Editorial change

Change Description

Parameter Change

In Protocol Stack of Iub (over IP), the NCP/CCP Bearing Type parameter in the ADD IUBCP command is renamed as Bear Type. The SET OMCH (BTS3812E, BTS3812AE, BBU3806, BBU3806C) command is changed to ADD OMCH (BTS3812E, BTS3812AE, BBU3806, BBU3806C).

The following parameter is deleted:

General documentation change:

None

z

Bear Type

Implementation information has been moved to a separate document. Transport Security of IP RAN is merged into 1.3.5 IP RAN VLAN

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NCP/CCP Bearing Type The following parameter is added: z

None


1-5


2 IP RAN Introduction

2

IP RAN Introduction

The IP Radio Access Network (RAN) feature enables IP transport on the Iub, Iur, and Iu interfaces. This makes it possible for the operators to use their existing IP networks in a larger and more flexible capacity. In this way, network deployment costs are reduced. The most widely used data communication networks are based on IP transport. Apart from being more economical than the Asynchronous Transfer Mode (ATM) network, the IP networks offer multiple access modes and provide enough transmission bandwidth for high speed data services, such as High Speed Downlink Packet Access (HSDPA).

IP Interface Boards To implement the IP RAN feature, the RNC and the NodeB must be configured with the related IP interface boards. The IP interface boards are as follows: z

z

IP interface boards for the RNC −

PEUa

−

FG2a

−

GOUa

−

UOIa

−

POUa

IP interface board for the NodeB −

The HBBU of earlier versions provides Fast Ethernet (FE) ports. Therefore, no hardware change is necessary.

−

The BTS3812E and the BTS3812AE require the Universal Transport Interface Unit (NUTI) board. The NUTI board provides eight E1/T1 ports and two FE ports.

−

The WMPT board provides 4 E1/T1 ports and 2 FE ports, the UTRP board provides 8 E1/T1 ports.

Numbering Schemes Numbering schemes are used for this feature for FE, GE and E1/T1 ports of the NodeB and the RNC, and for the RNC Point-to-Point Protocol (PPP) links. Numbering Scheme for FE, GE and E1/T1 Ports

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Table 2-1 describes the numbering scheme for the FE, GE, and E1/T1 ports on the NodeB and the RNC. Table 2-1 Numbering scheme for the FE, GE and E1/T1 ports on the NodeB and the RNC Board RNC

Port Type and Number PEUa

E1/T1: 0 to 31

FG2a

FE: 0 to 7 Electrical GE: 0 to 1 (corresponding to 0 and 3 of the FE port number).

GOUa

Optical GE: 0 to 1

UOIa

Unchannelized optical STM-1/OC-3c: 0 to 3

POUa

E1: 0 to 125 T1: 0 to 167

NodeB

NUTI

FE: 0 to 1 E1/T1: 0 to 7

BBU

FE: 0 to 1 E1/T1: 0 to 7

WMPT

FE: 0 to 1 E1/T1: 0 to 3

UTRP

E1/T1: 0 to 7

NOTE: BBU = Baseband Unit

Numbering Scheme for RNC PPP Links The numbering scheme that corresponds to the PEUa, POUa, and UOIa for PPP links at the RNC is as follows: z

PEUa: 0 to 127

z

POUa: 0 to 167

z

UOIa: 0 to 3

Numbering Scheme for NodeB PPP Links The numbering scheme that corresponds to the HBBU, NUTI, WMPT, and UTRP for PPP links at the NodeB is as follows:

2-2

z

HBBU: 0 to 15

z

NUTI: 0 to 15

z

WMPT: 0 to 7

z

UTRP: 0 to 15


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Impact z

Impact on System Performance This feature has no impact on system performance.

z

Impact on Other Features This feature has no impact on other features.

Network Elements Involved Table 2-2 describes the Network Elements (NEs) involved in IP RAN. Table 2-2 NEs involved in IP RAN UE

NodeB

RNC

MSC Server

MGW

SGSN

GGSN

HLR

–

√

√

√

√

√

–

–

NOTE: z –: not involved z

√: involved

UE = User Equipment, RNC = Radio Network Controller, MSC = Mobile Service Switching Center, MGW = Media Gateway, SGSN = Serving GPRS Support Node, GGSN = Gateway GPRS Support Node, HLR = Home Location Register

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3 IP RAN Principles

3

IP RAN Principles

The following lists the contents of this chapter. z

IP RAN Application Scenarios

z

IP RAN Protocol Stacks

z

IP Addresses and Routes of IP RAN

z

IP RAN QoS

z

IP RAN VLAN

z

IP RAN FP-Mux

z

IP RAN Header Compression

z

IP RAN Redundancy

z

IP RAN Load Sharing

z

IP RAN DHCP

z

IP RAN Transport Capabilities

3.1 IP RAN Application Scenarios The IP RAN application scenarios consist of: z

Iub over Time Division Multiplexing (TDM) Network

z

Iub over IP Network

z

Iub over hybrid IP transport Network

z

Iub over IP/ATM Network

z

Iu/Iur over IP Network.

3.1.1 Iub over TDM Network Figure 3-1 shows the TDM networking mode.

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3 IP RAN Principles

Figure 3-1 TDM networking mode

In the TDM networking mode, the RNC uses the PEUa and POUa as the Iub interface boards, and the NodeB uses the HBBU, NUTI, WMPT, and UTRP as the Iub interface boards. The RNC and NodeBs support IP over E1/T1, which is based on Plesiochronous Digital Hierarchy (PDH) or Synchronous Digital Hierarchy (SDH). The TDM network ensures the reliability, security, and QoS of the Iub interface data transmission, but the costs of E1 transport are relatively high.

3.1.2 Iub over IP Network Figure 3-2 shows the IP networking mode. Figure 3-2 IP networking mode

In the IP networking mode: z

The FG2a or GOUa board of the RNC serves as the Iub interface board and supports board backup, FE/GE port backup, or FE/GE port load sharing.

z

The HBBU, NUTI, or WMPT board of the NodeB serves as the Iub interface board, and the NodeB is connected to the IP network through FE port.

The IP network can be any of the following types: z

3-2

Layer 2 network, for example, metropolitan area Ethernet and VPLS


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3 IP RAN Principles

z

Layer 3 network, for example, IP/MPLS/VPN

z

Multi-Service Transmission Platform (MSTP) network

3.1.3 Iub over Hybrid IP Transport Network Figure 3-3 shows the hybrid IP networking mode. Figure 3-3 Hybrid networking mode

In this networking mode: z

The PEUa/POUa and FG2a/GOUa boards of the RNC serve as the Iub interface boards and support FG2a/GOUa board backup, FE/GE port backup, or FE/GE port load sharing. The POUa supports the board with Multiplex Section Protection (MSP) backup mode, and port wih MSP backup mode.

z

The NodeB is connected to the IP network through FE port and uses the HBBU, NUTI or WMPT as the Iub interface board.

z

The NodeB is connected to the TDM network through E1/T1 port and uses the HBBU, NUTI, UTRP, or WMPT as the Iub interface board.

In Hybrid IP transport, services with different QoS requirements can be transmitted in different paths. The two paths from the RNC to the NodeB are connected to two different networks through different ports, or through the same port that is connected to the external data equipment according to Differentiated Service Code Point (DSCP). z

Low QoS network (IP network, such as Ethernet) The PS interactive and background services that have low QoS are carried on the low QoS network. When the bandwidth of the low QoS network is limited, low QoS services are carried on the high QoS network.

z

High QoS network (TDM network, such as PDH and SDH) The control plane data, Radio Resource Control (RRC) signaling, common channel data, Circuit Switched (CS) services, Packet Switched (PS) conversational services, and streaming services are carried on the high QoS network. When the bandwidth of the high QoS network is limited, the RNC reduces the rate of the low QoS services that are carried on the high QoS network, or the RNC rejects the access of high QoS services if no low QoS services are carried on the high QoS network.

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3 IP RAN Principles

The hybrid transport network is flexible in terms of meeting different QoS requirements, but it is complicated to manage.

3.1.4 Iub over IP/ATM Network With the development of data services, especially with the introduction of High Speed Packet Access (HSPA), the Iub interface has an increasing demand for the bandwidth. A single ATM network has high costs. IP transport saves the transmission cost but provides a lower guarantee of QoS than ATM transport does. Therefore, the ATM/IP networking mode is introduced. Services with different QoS requirements are transmitted on different types of network. Figure 3-4 shows the ATM/IP networking mode. Figure 3-4 ATM/IP networking mode

The ATM/IP networking mode allows hybrid transport of services with different QoS requirements. High QoS services, such as voice services, streaming services, and signaling, are transmitted on the ATM network. Low QoS services, such as PS Best Effort (BE) services, are transmitted on the IP network. The ATM and IP interface boards of the RNC must be configured to support this networking mode. The ATM interface board can be the AEUa, AOUa, or UOIa. The IP interface board can be the FG2a, GOUa, UOIa, POUa, or PEUa. z

The RNC is connected to the ATM network through the E1/T1 or STM-1 port.

z

The RNC is connected to the IP network through the FE/GE port.

The NodeB is connected to the ATM/IP networks through the ATM and IP interface boards respectively. The ATM interface board can be the HBBU, NUTI, or WMPT. The IP interface board can be the HBBU, NUTI, WMPT or UTRP. z

The NodeB is connected to the high QoS ATM network through E1/T1 port.

z

The NodeB is connected to the low QoS IP network through FE port. The NodeB cannot be connected to both the ATM network and the IP network simultaneously through E1/T1 ports on the same board.

In the ATM/IP network, the ATM network ensures the QoS, while the IP network reduces the transmission costs and fulfills the requirement of high-speed data services for high bandwidth on the Iub interface. On the other hand, the ATM/IP network requires the maintenance of both the ATM and the IP networks; thus the maintenance is more complex and expensive.

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3 IP RAN Principles

3.1.5 Iu/Iur over IP Network Figure 3-5 shows the Iu/Iur networking mode. Figure 3-5 Iu/Iur over IP network

In this networking mode, the FG2a, GOUa, or UOIa board of the RNC serves as the Iu or Iur interface board and supports board backup, FE/GE port backup, or FE/GE port load sharing. The IP network can be any of the following three types: z

Layer 2 network, for example, metropolitan area Ethernet and VPLS

z

Layer 3 network, for example, IP/MPLS VPN

z

Multi-Service Transmission Platform (MSTP) network

3.2 IP RAN Protocol Stacks The IP RAN protocol stacks consist of: z

Protocol Stack of Iub (over IP)

z

Protocol Stack of Hybrid Iub (over IP /TM)

z

Protocol Stack of Iu-CS (over IP)

z

Protocol Stack of Iu-PS (over IP)

z

Protocol Stack of Iur (over IP)

z

Protocols of Data Link Layer

3.2.1 Protocol Stack of Iub (over IP) The protocol stack of Iub (over IP) is the Iub IP protocol. Data transmission on the Iub interface is based on the IP transport.

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3 IP RAN Principles

Figure 3-6 Protocol stack of Iub (over IP)

Figure 3-6 shows the protocol stack of Iub (over IP). z

The control plane data is carried on the SCTP link.

z

The user plane data is carried on the IP path.

z

The data link layer can use IP over E1/T1, IP over Ethernet, IP over E1/T1 over SDH, or IP over SDH.

Transport Mode Configuration on the RNC Side To support Iub (over IP), associated parameters are configured as follows: z

The IUB trans bearer type parameter is set to IP_TRANS.

z

The IP Trans Apart Ind parameter is set to SUPPORT or NOT_SUPPORT to specify whether the hybrid IP transport is applied.

z

The Adjacent Node Type parameter is set to IUB.

z

The Transport Type parameter is set to IP.

Transport Mode Configuration on the NodeB Side If E1/T1 is used for transport on the NodeB side, the Bearing Mode parameter for E1/T1 must be set to IPV4.

IP Path An IP path is a group of connections between the RNC and the NodeB. An Iub interface has at least one IP path. It is recommended that more than one IP path be planned.

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IP Path Configuration on the RNC Side The parameters for establishing an IP path on the RNC side are as follows: z

Local IP address

z

Peer IP address

z

Peer subnet mask

z

IP path type

z

DSCP

IP Path Configuration on the NodeB Side The parameters for establishing an IP path on the NodeB side are as follows: z

Port Type

z

NodeB IP address

z

RNC IP address

z

Traffic Type

z

Differentiated Services Code Point

SCTP Link An SCTP link carries signaling messages on the Iub interface. The signaling messages carried on the SCTP link are classified into NCP and CCP, as described in Table 3-1. Table 3-1 Signaling messages carried on SCTP links Type

Description

NCP

An NCP carries common process messages of NBAP over the Iub interface. An Iub interface has only one NCP.

CCP

A CCP carries dedicated process messages of NBAP over the Iub interface. An Iub interface may have multiple CCPs. The number of CCPs depends on network planning.

NOTE: NCP = NodeB Control Port, CCP = Communication Control Port

The Signalling link mode of an SCTP link can be SERVER or CLIENT.

SCTP Link Configuration on the RNC side Iub control plane data is carried on the SCTP link. An SCTP endpoint can use two local addresses, but these two must use the same port number. This mechanism is called multi-homing. In Iub IP transport, the Signalling link mode parameter has to be set to SERVER when you configure an SCTP link on the RNC side. The other parameters for establishing an SCTP link on the RNC side are as follows:

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3 IP RAN Principles z

First local IP address

z

Second local IP address

z

First destination IP address

z

Second destination IP address

z

Local SCTP port No.

z

Destination SCTP port No. The second local IP address and the second peer IP address must be configured together.

NCP and CCP Configuration on the RNC Side On the RNC side, the NodeB Control Port (NCP) link and Communication Control Port (CCP) link are carried on the SCTP link. That is, the Bearing link type parameter has to be set to SCTP. The parameters for establishing the NCP link and CCP link are as follows: z

SCTP link No.

z

Bearing link type

SCTP Link Configuration on the NodeB Side The parameters for establishing an SCTP link on the NodeB side are as follows: z

Local IP address

z

Second Local IP address

z

Peer IP address

z

Second Peer IP address

z

Local SCTP Port

z

Peer SCTP Port

NCP and CCP Configuration on the NodeB Side On the NodeB side, the NCP link and CCP link are carried on the SCTP link. That is, the NCP/CCP Bearing Type parameter has to be set to IPV4.

OM Channel OM channel is used to maintain and configure the NodeB remotely. There are two methods to configure routes for the OM channel on the Iub interface: z

Configuring routes between the M2000 and the NodeB through the RNC.

z

Configuring routes between the M2000 and the NodeB not through the RNC.

Figure 3-7 shows an example of configuring routes between the M2000 and the NodeB through the RNC.

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3 IP RAN Principles

Figure 3-7 Example of configuring routes between the M2000 and the NodeB through the RNC

Figure 3-7 takes layer 2 networking on the Iub interface as an example. When layer 3 networking is applied to the Iub interface, the IP interface board and the NodeB communicate through a router.

If the OM subnet where the M2000 is located is connected to the IP network that covers the NodeB, the routes can be configured between the M2000 and the NodeB not through the RNC. Figure 3-8 shows an example of configuring routes between the M2000 and the NodeB not through the RNC. Figure 3-8 Example of configuring routes between the M2000 and the NodeB not through the RNC

OM Channel Configuration on the RNC Side For detailed information about the OM channel configuration on the RNC side, see 3.10 IP RAN DHCP.

OM Channel Configuration on the NodeB Side The parameters for establishing an OM channel on the NodeB side are as follows: z

Local IP Address

z

Local IP Mask

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3 IP RAN Principles z

Peer IP address

z

Peer IP Mask

z

Bear Type

Other Data Configuration on the RNC Side and NodeB Side To enable Iub (over IP) transport, the other data (such as the physical layer data, data link layer data, mapping between transmission and traffic, and factor table) has to be configured. For detailed information about these configurations, refer to the RNC Initial Configuration Guide and the NodeB Initial Configuration Guide.

3.2.2 Protocol Stack of Hybrid Iub (over IP /TM) In hybrid Iub transmission (over IP/ATM), data transmission on the Iub interface is based on both ATM transport and IP transport. Figure 3-9 Protocol stack of Iub (over IP/ATM)

Figure 3-9 shows the protocol stack of Iub (over IP/ATM). With the introduction of Iub (over IP/ATM), the data between RNC and NodeB can be transmitted on two networks: ATM network and IP network. z

z

On the ATM network −

Iub control plane data is carried on the SAAL link.

−

Iub user plane data is carried on the AAL2 path.

On the IP network −

3-10

Iub control plane data is carried on the SCTP link.


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Iub user plane data is carried on the IP path.

Transport Mode Configuration on the RNC Side To support Iub (over ATM/IP), associated parameters are configured as follows: z

The IUB trans bearer type parameter is set to ATMANDIP_TRANS.

z

The Adjacent Node Type parameter is set to IUB.

z

The Transport Type parameter is set to ATM_IP.

IP Path and SCTP Link Configuration on the RNC and NodeB Sides The parameters for IP path and SCTP link on the RNC and NodeB sides are similar to those for Iub (over IP). For detailed information, see 3.2.1 Protocol Stack of Iub (over IP).

AAL2 Path An AAL2 path is a group of connections between the RNC and the NodeB. An Iub interface has at least one AAL2 path. It is recommended more than one AAL2 path be planned. An AAL2 path is carried on a PVC. The PVC identifier (VPI/VCI) and other attributes of the PVC must be negotiated between the RNC and the NodeB.

AAL2 Path Configuration on the RNC Side The parameters for establishing an AAL2 path on the RNC side are as follows: z

Adjacent node ID

z

AAL2 path ID

For detailed information about AAL2 path resources, see ATM Transmission Resources.

AAL2 Path Configuration on the NodeB Side The parameters for establishing an AAL2 path on the NodeB side are as follows: z

AAL2 path ID

z

Node Type

z

Path Type

SAAL Link of User Network Interface (UNI) Type An SAAL link of UNI type carries signaling messages on the Iub interface. The signaling messages carried on the SAAL links are categorized into NCP, CCP, and ALCAP, as described in Table 3-2: Table 3-2 The type of the signaling messages carried on the SAAL links Type

Description

NCP

An NCP carries common process messages of NBAP over the Iub interface. The Iub interface has only one NCP.

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Type

Description

CCP

A CCP carries dedicated process messages of NBAP over the Iub interface. The Iub interface may have multiple CCPs. The number of CCPs depends on network planning.

ALCAP

The ALCAP is also called Q.AAL2. Typically, the Iub interface has one ALCAP.

An SAAL link of UNI type is carried on a PVC. The PVC identifier (VPI/VCI) and other attributes of the PVC must be negotiated between the RNC and the NodeB.

SAAL Link Configuration on the RNC Side The parameters for establishing an SAAL link on the RNC side are described as follows: z

Interface type

z

Bearing VPI

z

Bearing VCI

NCP and CCP Configuration on the RNC Side It is recommended that all Iub control plane data be carried on the ATM network when Iub is carried on both ATM and IP. In this case, Bearing link type of the NCP and CCP should be set to SAAL. z

Bearing link type

z

SAAL link No.

SAAL Link Configuration on the NodeB Side The parameters for establishing an SAAL link on the NodeB side are as follows: z

Bearing VPI

z

Bearing VCI

NCP and CCP Configuration on the NodeB Side It is recommended that all Iub control plane data be carried on the ATM network when Iub is carried on both ATM and IP. In this case, NCP/CCP Bearing Type of the NCP and CCP should be set to ATM.

OM Channel Configuration on the RNC and NodeB Sides The parameters for OM channel on the RNC side and NodeB side are similar to those for Iub (over IP). For detailed information, see 3.2.1 Protocol Stack of Iub (over IP).

Other Data Configuration on the RNC and NodeB Sides To enable Iub (over ATM/IP) transport, the other data (such as the physical layer data, data link layer data, mapping between transmission and traffic, and factor table) has to be

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configured. For detailed information about these configurations, refer to the RNC Initial Configuration Guide and the NodeB Initial Configuration Guide.

3.2.3 Protocol Stack of Iu-CS (over IP) The protocol stack of Iu-CS (over IP) is the Iu-CS IP protocol. Data transmission on the Iu-CS interface is based on the IP transport. Figure 3-10 Protocol stack of Iu-CS (over IP)

Figure 3-10 shows the protocol stack of Iu-CS (over IP). z


z


Transport Mode Configuration on the RNC Side To support Iu-CS (over IP), associated parameters are configured as follows: z

The CN domain ID parameter is set to CS_DOMAIN.

z

The IU transfers bearer type parameter is set to IP_TRANS.

z

The Adjacent Node Type parameter is set to IUCS.

z


IP Path Configuration on the RNC Side The parameters for IP path on the RNC side are similar to those for Iub (over IP). For details, see 3.2.1 Protocol Stack of Iub (over IP).

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SCTP Link Configuration on the RNC Side The parameters for SCTP link on the RNC side are similar to those for Iub (over IP). For details, see 3.2.1 Protocol Stack of Iub (over IP).

Other Data Configuration on the RNC Side To enable Iu-CS (over IP) transport, the other data (such as the physical layer data, data link layer data, mapping between transmission and traffic, factor table, and data of M3UA) has to be configured. For details about these configurations, refer to the RNC Initial Configuration Guide.

3.2.4 Protocol Stack of Iu-PS (over IP) The protocol stack of Iu-PS (over IP) is Iu-PS IP protocol. Data transmission on the Iu-PS interface is based on the IP transport. Figure 3-11 Protocol stack of Iu-PS (over IP)

Figure 3-11 shows the protocol stack of Iu-PS (over IP). z


z


Transport Mode Configuration on the RNC Side To support Iu-PS (over IP), associated parameters are configured as follows:

3-14

z

The CN domain ID parameter is set to PS_DOMAIN.

z

The IU transfers bearer type parameter is set to IP_TRANS.

z

The Adjacent Node Type parameter is set to IUPS.

z



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The parameters for transport mode are similar to those for Iu-CS (over IP). For detailed information, see 3.2.3 Protocol Stack of Iu-CS (over IP).

IP Path Configuration on the RNC Side The parameters for IP path on the RNC side are similar to those for Iub (over IP). For detailed information, see 3.2.1 Protocol Stack of Iub (over IP).

SCTP Link Configuration on the RNC Side The parameters for SCTP link on the RNC side are similar to those for Iub (over IP). For detailed information, see 3.2.1 Protocol Stack of Iub (over IP)..

Other Data Configuration on the RNC Side To enable Iu-PS (over IP) transport, the other data (such as the physical layer data, data link layer data, mapping between transmission and traffic, factor table, and data of M3UA) has to be configured. For detailed information about these configurations, refer to the RNC Initial Configuration Guide.

3.2.5 Protocol Stack of Iur (over IP) The protocol stack of Iur (over IP) is Iur IP protocol. Data transmission on the Iur interface is based on the IP transport. Figure 3-12 Protocol stack of Iur (over IP)

Figure 3-12 shows the protocol stack of Iur (over IP), where: z


z


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Transport Mode Configuration on the RNC Side To support Iur (over IP), associated parameters are configured as follows: z

The Iur Interface Existing Indication parameter is set to TRUE.

z

The IUR trans bearer type parameter is set to IP_TRANS.

z

The Adjacent Node Type parameter is set to IUR.

z


IP Path Configuration on the RNC Side The parameters for IP path on the RNC side are similar to those for Iub (over IP). For detailed information, see 3.2.1 Protocol Stack of Iub (over IP)..

SCTP Link Configuration on the RNC Side The parameters for SCTP link on the RNC side are similar to those for Iub (over IP). For detailed information, see 3.2.1 Protocol Stack of Iub (over IP)..

Other Data Configuration on the RNC Side To enable Iur (over IP) transport, the other data (such as the physical layer data, data link layer data, mapping between transmission and traffic, factor table, and data of M3UA) has to be configured. For detailed information about these configurations, refer to the RNC Initial Configuration Guide.

3.2.6 Protocols of Data Link Layer The protocols at the data link layer consist of Ethernet, PPP/MLPPP, MCPPP, and PPPMux.

Ethernet Ethernet is a standard that was jointly released by Digital Equipment Corp., Intel Corp., and Xerox in 1982. It is the most widely used Local Area Network (LAN) technology based on TCP/IP and CSMA/CD access method. The MAC addressing scheme of Ethernet helps to resolve the addressing problem of entities within the Ethernet. Each MAC address has 48 bits and the addresses are assigned worldwide under the same rule. The earliest Ethernet packet encapsulation format complies with Ethernet 802.3 defined by IEEE and the most common format now is Ethernet II specified by RFC0826. The NodeB and the RNC can transmit frames in Ethernet II format and receive frames in Ethernet 802.3 and Ethernet II formats.

PPP/MLPPP The PPP provides standard methods for encapsulating the multi-protocol datagrams on point-to-point links. These datagrams consist of IP, IPX, and Apple Talk. MLPPP (MP) is used to combine multiple physical links into a logical link. Therefore, it provides a relatively high bandwidth and facilitates quick data transfer. MLPPP implementation is shown in Figure 3-13.

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Figure 3-13 MLPPP implementation

MCPPP MCPPP (MC) is an extension of the MLPPP protocol and provides more priorities. Packets with a higher priority can interrupt the transmission of those with a lower priority. The MC protocol is implemented in compliance with RFC2686. The bits, responsible for marking the priority of a packet, in the MLPPP header are not used in the MLPPP protocol. These bits are the two bits after the E flag bit in the short sequence, or the four bits after the E flag bit in the long sequence. Packets at each priority level have their own MLPPP mechanism, for example, independent sequence number and reassembly queue. z

The parameter on the RNC side is MLPPP type.

z

The parameter on the NodeB side is Multi Class PPP.

PPPMux PPPMux encapsulates multiple PPP frames (also called subframes) in a single PPPMux frame. The subframes in the PPPMux frame are distinguished by delimiters. PPPMux reduces PPP overhead per packet and improves bandwidth efficiency. PPPMux is implemented in compliance with RFC3153. z

The parameter on the RNC side is PPP mux.

z

The parameter on the NodeB side is PPP MuxCP.

3.3 IP Addresses and Routes of IP RAN This section describes the IP addresses and routes that are required for running an IP RAN network.

3.3.1 Two Networking Types on the Iub/Iur/Iu-CS/Iu-PS Interfaces There are two types of networking on the Iub/Iur/Iu-CS/Iu-PS interfaces: layer 2 networking and layer 3 networking. Layer 2 Networking Compared with layer 3 networking, layer 2 networking is simpler. That is because the port IP addresses of the RNC, NodeB, and neighboring RNC, MGW and SGSN are located in the same network segment and no route is required.

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Figure 3-14 shows an example of layer 2 networking on the Iub/Iur/Iu-CS/Iu-PS interfaces. Figure 3-14 Layer 2 networking on the Iub/Iur/Iu-CS/Iu-PS interfaces

z

IP 1 is the interface IP address on the IP interface board.

z

In layer 2 networking mode, the interface IP addresses of the RNC and NodeBs are in the same network segment. A route is not necessary in this case, which makes the networking relatively simple.

Layer 3 Networking Figure 3-15 shows an example of layer 3 networking on the Iub/Iur/Iu-CS/Iu-PS interface. Figure 3-15 Layer 3 networking on the Iub/Iur/Iu-CS/Iu-PS interface

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z

IP 1 and IP 2 are device IP addresses of the IP interface board. One interface board supports a maximum of five device IP addresses. The device IP addresses configured on the same interface board cannot be located in the same subnet.

z

IP 3 and IP 4 are port IP addresses of the IP interface board.

z

IP 5 and IP 6 are gateway IP addresses on the RNC side.

z

IP 7 is the gateway IP address on the NodeB/neighboring RNC/MGW/SGSN side.

z

IP 8 is the IP address of the NodeB/neighboring RNC/MGW/SGSN.

3.3.2 Route on the Iub/Iur/Iu-CS/Iu-PS Interface On the Iub/Iur/Iu-CS/Iu-PS interface where layer 2 networking is applied, no route is required. On the Iub/Iur/Iu-CS/Iu-PS interface where layer 3 networking is applied, you should configure the route, as described in Table 3-3 on the RNC. Table 3-3 Route on the Iub/Iur/Iu-CS/Iu-PS interface Part

Route Description

IP interface board

The route travels from the RNC to the network segment where the NodeB/neighboring RNC/MGW/SGSN is located. You can run the ADD IPRT command on the RNC to configure the route. Destination IP address is the address of the network segment where the NodeB/neighboring RNC/MGW/SGSN is located, and Forward route address, for example, IP 5 or IP 6, is the gateway IP address on the RNC side.

3.3.3 IP Addresses for SCTP Links and IP Paths Between RNC and NodeB Figure 3-16 shows the IP addresses assigned to SCTP links and IP paths between RNC and NodeB. Figure 3-16 IP addresses for SCTP links and IP paths between RNC and NodeB

IP1-0 and IP2-0: IP addresses for SCTP links on the NodeB side IP1-1 and IP2-1: IP addresses for SCTP links on the RNC side IP3-0: IP address for the IP paths on the NodeB side IP3-1: IP address for the IP paths on the RNC side

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Figure 3-16 shows two interconnected BBUs on the NodeB side as an example. When two BBUs are interconnected through the EIa ports, the two BBUs are regarded as one NodeB on the RNC side. On the NodeB side, BBU1, which is connected to the transport network between RNC and NodeB, is an active BBU, while BBU2 is a standby BBU. The IP addresses of the NodeB for communicating with the RNC are configured only on BBU1. The data of the Iub interface is sent or received through the FE/E1 ports of BBU1, as shown in Figure 3-16.

z

z

z

You can specify the active BBU and standby BBU by setting the Dual-In-line Package (DIP) switch. For detailed information about the DIP switch, see the description of the DIP switch on the BBU3806 or DIP switch on the BBU3806C in the DBS3800 Hardware Description.

z

Figure 3-16 shows the settings of the IP addresses for the SCTP links and the IP paths for NodeB V100R010. For NodeB V200R010 version, the settings are the same as those for NodeB V100R010. The only difference is that, for NodeB V200R010, there are no interconnected BBUs.

IP1-0 and IP 2-0 are configured as the first local IP address and the second local IP address respectively for the SCTP links on the NodeB side. IP1-1 and IP2-1 are configured accordingly on the RNC side. The first local IP address and the second local IP address cannot be the same. When the first local IP address for the SCTP links is unavailable, the data on the SCTP links is transmitted through the second local IP address. −

When the layer 2 or TDM networking is applied, IP1-0, IP1-1, IP2-0, and IP2-1 are the IP addresses of the port (FE/GE/PPP/MLPPP). IP1-0 and IP1-1 are within the same network segment, and the same is true for IP2-0 and IP2-1.

−

When the layer 3 networking is applied, IP1-0 and IP2-0 are the IP addresses of the FE ports, and IP1-1 and IP2-1 are the device IP addresses. IP1-0 and IP1-1 do not stay within the same network segment, and the same is true for IP2-0 and IP2-1.

IP paths between RNC and NodeB do not work in backup mode. −

When the layer 2 or TDM networking is applied, IP3-0 and IP3-1 are IP addresses of the port (FE/PPP/MLPPP). IP3-0 and IP3-1 are within the same network segment.

−

When the layer 3 networking is applied, IP3-0 is IP address of the FE port and IP3-1 is the device IP address. IP3-0 and IP3-1 do not stay within the same network segment.

3.4 IP RAN QoS The assurance mechanisms of QoS are implemented at the application layer, IP layer, data link layer, and physical layer. Table 3-4 describes the assurance mechanisms of the QoS. Table 3-4 Assurance mechanisms of the QoS

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Layer

Mechanism

Application layer

Admission control and congestion control

IP layer

Differentiated Service

Data link layer

Priority Queue (PQ)

Physical layer

Rate Limiting (RL) at the physical port


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3.4.1 Admission Control and Congestion Control For detailed information about admission control and congestion control, see Admission Control and Congestion Control.

3.4.2 Differentiated Service Figure 3-17 shows the differentiated service process. Figure 3-17 Differentiated service process

Table 3-5 describes the differentiated service process. The classification and adjustment of traffic usually happen at the network edge. Table 3-5 Differentiated service process Operation

Description

Classifying the service

Traffic classification enables different types of services that are implemented by setting different values.

Adjusting the service

Metering

The data rate is metered and the subsequent shaping and scheduling are based on the metering.

Marking

The packets are marked with different colors according to Traffic Conditioning Agreement (TCA).

Shaping

The packets in the traffic flow are delayed as required by the service model.

Dropping

Non-TCA-supportive packets are dropped.

The adjustment of service ensures that the traffic flow involving differentiated services complies with TCA.

3.4.3 PQ and RL The principles of PQ and RL are considered together. The PQs are configured automatically in the NodeB. When the actual bandwidth exceeds the specified bandwidth, the system buffers the congested data or discards it to ensure a specified bandwidth at the physical port. When the physical port is congested, the system discards the message with lower priority according to the PQ principle. Table 3-6 describes the rules for PQs based on the three Most Significant Bits (MSBs) of the DSCP. Issue 02 (2008-07-30)


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Table 3-6 Rules for PQs in NodeB MSBs of the DSCP

PQ

110 or 111

The urgent queue is used by default. No manual configuration of the PQ is necessary.

101

TOP

100 or 011

MIDDLE

010 or 001

NORMAL

0

BOTTOM

The parameters for setting the priorities for data transmission on the NodeB side are as follows: z

Signal Priority

z

OM priority

The RNC IP interface boards (PEUa/FG2a/GOUa/POUa/UOIa) support six priority queues numbered from 0 to 5 in a descending order. The top two priority queues adopt PQ scheduling and the other four queues of lower priority employ Weighted Round Robin (WRR) scheduling. For details of the mapping between the DSCP values and the IP port queues, refer to Differentiated Service in Transmission Resource Management document.

3.5 IP RAN VLAN Virtual Local Area Network (VLAN) enhances the IP transport security. Besides, VLAN provides the priority service and isolates different users.

3.5.1 Ensuring Security Compared with the TDM network, the IP network has relatively low security. VLAN combined with Virtual Private Network (VPN), however, ensures the IP transport security. Figure 3-18 shows the VLAN and VPN implementation. The security of VLANs is implemented at the NodeB and the RNC, and that of the VPNs is implemented by external equipment. Figure 3-18 IP network security

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3.5.2 Providing Priority Service Figure 3-19 shows a typical example of the VLAN solution on the VLAN on the Iub interface. In this solution, the Multi-Service Transmission Platform (MSTP) network provides two Ethernets carried on two Virtual Channel (VC) trunks, respectively. z

One Ethernet is a private network for the real-time services of multiple NodeBs without the influence of other customers. This Ethernet is used to carry services of high priority.

z

The other Ethernet is a public network for the non-real-time services of multiple NodeBs and can be shared with other customers. The services are prone to the influence of other customers. Thus, this Ethernet is used to carry services of low priority.

Figure 3-19 Typical solution of the VLAN on Iub

Red line: private network Blue line: public network Black line: connection between the routers

The VLANID Flag parameter indicates whether VLAN is enabled or not. The NodeB and the RNC identify the service QoS through Vlan priority in the VLAN tag. Each NodeB or the RNC provides an Ethernet port to connect to the MSTP network. The MSTP transmits the Ethernet data to either of the VC trunks according to Vlan priority in the VLAN tag. Each VC trunk supports up to two QoS classes. In the same VC trunk, the data of different NodeBs is identified by different VLAN ID parameters. The VLAN tag contains a 2-byte Tag Protocol Identifier (TPID) and a 2-byte Tag Control Information (TCI). z

TPID is defined by the IEEE and is used to indicate that the frame is attached with an 802.1Q tag. VLAN TPID has a fixed value 0x8100.

z

TCI contains the frame control information and consists of the following items:

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Priority: a 3-bit field that indicates the frame priority. The eight values, from 0 to 7, represent eight priorities. The priority field is defined in the IEEE 802.1Q protocol.

−

Canonical Format Indicator (CFI): a 1-bit field. The value 0 indicates the canonical format and 1 indicates the non-canonical format. CFI specifies the bit sequence of the address contained in the encapsulated frame in the token ring or source route FDDI media access method.


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VLAN Identifier (VLAN ID): a 12-bit field that indicates the VLAN ID. It represents 4096 IDs. The frame, which complies with 802.1Q, contains this field and indicates which VLAN the frame belongs to.

The NodeB attaches VLAN tags to the frames that are sent from the Ethernet port, but does not attach VLAN tags to the frames that are received from the Ethernet port. When the NodeB supports the VLAN, it attaches diverse tags to different traffic flows to enable the traffic flow transmission in different VLAN channels. The parameters on the NodeB side are as follows: z

Traffic Type

z

User Data Service Priority

z

Insert VLAN Tag

z

Vlan Id

z

Vlan priority On the RNC side, the NodeB detection function can be started through the MML command STR NODEBDETECT in order to periodically send the VLAN IDs to the NodeBs. By this means, when a new NodeB is set up or a NodeB recovers from the fault, the NodeB can automatically obtain its VLAN ID from the RNC.

3.6 IP RAN FP-Mux Frame Protocol Multiplexing (FP-Mux) encapsulates multiple small FP PDU frames (also called subframes) into a UDP package, thus improving the transport efficiency. FP-Mux is only applicable to the user plane data on the Iub interface based on UDP/IP. Figure 3-20 shows the UDP/IP package format when FP-Mux is applied. Figure 3-20 FP-Mux UDP/IP package format

To enable FP-Mux, the FPMUX flag parameter has to be set to YES. Max subframe length indicates the maximum length of the subframe. Maximum Frame Length indicates the

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maximum length of the frame of the FP-Mux UPD/IP package. The UDP package frame is sent out once the time set by FPTIME expires. FP-Mux is applicable to frames with the same priority, that is, frames of the same DSCP value.

3.7 IP RAN Header Compression Header compression is used to reduce protocol header overhead of point-to-point links and to improve bandwidth efficiency. The RNC and the NodeB support the following three header compression methods: z

Address and Control Field Compression (ACFC)

z

Protocol Field Compression (PFC)

z

IP Header Compression (IPHC)

3.7.1 ACFC ACFC, which complies with RFC 1661, is used to compress the address and control fields of PPP protocol. These fields usually contain constant values for PPP links. It is unnecessary to transport the whole fields every time. If ACFC passes the negotiation during the PPP Link Control Protocol (LCP), the address and control fields (0xFF03) of subsequent packets can be compressed.

3.7.2 PFC PFC, which complies with RFC 1661, is used to compress the protocol field of PPP. PFC can compress the 2-byte protocol field into a 1-byte one. The compression complies with the ISO3309 extension mechanism, that is, a binary 0 in the Least Significant Bit (LSB) indicates that the protocol field contains two bytes, and the other byte follows this byte. And a binary 1 in the LSB indicates that the protocol field contains one byte, and this byte is the last one. The majority of packets are compressible, because the protocol fields assigned are usually less than 256.

3.7.3 IPHC IPHC, which complies with RFC 2507 and RFC 3544, is used to compress the IP/UDP header of PPP links. IPHC improves bandwidth efficiency in the following two ways: z

The unchanged header fields in packet (IP/UDP) headers are not carried by each packet.

z

The header fields that vary with specified modes are replaced with fewer bits.

The header context is established on both ends of a link when packets with complete headers are sent occasionally. Thus the compressed packets can retrieve their original headers according to the context and the changed fields. z

The parameter on the RNC side is Head compress.

z

The parameter on the NodeB side is IP Header Compress.

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3.8 IP RAN Redundancy IP RAN Redundancy discusses the redundancy mechanism on the RNC side. The redundancy of IP RAN helps to improve the reliability of IP transport. On the NodeB side, for distributed NodeBs, the interconnection of two BBUs can enhance the baseband processing capability but cannot support the transmission backup.

3.8.1 Single-Homing Layer 3 Networking In the single-homing layer 3 networking, the FG2a or GOUa board of the RNC serves as the interface board and supports board backup and FE/GE port backup. Figure 3-21 shows the single-homing layer 3 networking. The FE/GE ports on the RNC serve the IP transport. Figure 3-21 Single-homing layer 3 networking

In this networking mode, the FE/GE ports of the RNC are configured for backup. The active and standby FE/GE ports of the RNC are connected to the Provider Edge (PE), which are further connected to the IP network. The active and standby FE/GE ports of the RNC share one IP address, IP 1-0. The PE configures the active and standby ports of the RNC in one VLAN and uses one interface IP address of the VLAN, IP 1-1. The GE optical ports on the GOUa board are applicable when the RNC is far away from the PE, and the FE/GE electrical ports on the FG2a board are applicable when the distance between the RNC and the PE is within 100 m.

3.8.2 Dual-Homing Layer 3 Networking In the dual-homing layer 3 networking, the FG2a or GOUa board of the RNC serves as the interface board and supports board backup and FE/GE port backup. Figure 3-22 shows the dual-homing layer 3 networking. The FE/GE ports on the RNC serve the IP transport.

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Figure 3-22 Dual-homing layer 3 networking

In this networking mode, the FE/GE ports of the RNC are configured for backup. The active and standby FE/GE ports of the RNC are connected to two PEs, which are further connected to the IP network. Complying with the Virtual Router Redundancy Protocol (VRRP), the two PEs provide redundancy-based protection for the data transmitted from the RNC. One PE connects to the other through two GE ports. Link Aggregation (LAG) is applied to the interconnection links between the PEs to increase the bandwidth and reliability of the links. The active and standby FE/GE ports of the RNC share one IP address, IP 1-0. The PEs configure the active and standby ports of the RNC in one VLAN and use one virtual VRRP IP address, IP 1-1. The GE optical ports on the GOUa board are applicable when the RNC is far away from the PE, and the FE/GE electrical ports on the FG2a board are applicable when the distance between the RNC and the PE is within 100 m.

3.8.3 Advantages and Disadvantages of the Networking Single-homing layer 3 networking provides redundancy-based protection for FE/GE links. The single PE saves the networking costs, but cannot provide PE-level protection. Dual-homing layer 3 networking provides redundancy-based protection not only for FE/GE links, but also for PE devices. But the dual PEs have high networking costs.

3.8.4 Configuration on the RNC Side To support the backup of the interface board, the Backup parameter has to be set to YES. The parameters on the RNC side are as follows: z

Board type

z

Backup

When the interface board is set to the backup mode, run the ADD ETHREDPORT command to set the backup mode of the associated ports. The parameter involved is Port No.. For detailed information about board redundancy and port redundancy, see RNC Parts Reliability in the RNC Product Description.

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3.8.5 Fault Detection In addition to the UP/DOWN detection performed at the physical link layer, the fault detection between the RNC and the Provider Edge (PE) involves the Bidirectional Forwarding Detection (BFD) and Address Resolution Protocol (ARP) detection. The BFD or ARP detection are applied on the layer 3 (L3) detection, which can also detect other faults, such as soft transfer. When the BFD or ARP detection finds a fault, the switchover between FE/GE ports will be triggered. The application of the BFD or ARP detection can increase the fault detection rate and enhance the reliability. The BFD is preferred since it has a quick and bidirectional detection. z

The ARP detection is used only when the peer equipment does not support the BFD, because the ARP detection is unidirectional.

z

The ARP message is a broadcast message; therefore, if there is a relatively large L2 broadcast domain between the RNC and the L3 equipment, a broadcast storm may easily occur. But if the RNC and the L3 equipment are directly connected, a broadcast storm never occurs.

The following tables describe the parameters of the Fault Detection: z

z

Gateway IP address Backup port IP address Backup port mask Backup port gateway IP address

z

Check type

z

Port work mode

z

Min interval of BFD packet send [ms]

z

Min interval of BFD packet receive [ms] detect multiplier of BFD packet

z z

z

3.9 IP RAN Load Sharing IP RAN load sharing improves the transport efficiency of IP RAN. Load sharing between FE/GE ports of the RNC is applicable to layer 3 networking between the RNC and other NEs, instead of layer 2 networking.

3.9.1 Load Sharing Layer 3 Networking The RNC supports load sharing between FE/GE ports that are located either on the same board or on the active and standby boards. The RNC supports load sharing between up to three FE/GE ports. Figure 3-23 shows the load sharing layer 3 networking of IP RAN. If there are two ports for load sharing, they are located on the active and standby boards.

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Figure 3-23 Load sharing layer 3 networking

In this scenario, the FG2a or GOUa board of the RNC serves as the interface board, and supports board backup and FE/GE port apart. The two FE/GE ports on the active and standby boards are configured with IP addresses of different network segments, IP 1-0 and IP 2-0. The PE configures the corresponding IP addresses, IP 1-1 and IP 2-1. The data to the destination IP address is shared by the two routes. The load sharing ports on the RNC can be connected to one PE or two different PEs.

3.9.2 Advantage and Disadvantage of the Networking In the load sharing layer 3 networking, the data traffic is shared by the ports to avoid the occasion when some ports are busy while others are idle, thus improving the transmission efficiency. This network solution, however, does not provide redundancy for data transmission. A port failure will lead to the decline of transmission capacity.

3.9.3 Configuration on the RNC Side To support the load sharing between the ports located on the active and standby boards, the Backup parameter should be set to NO. For detailed information about the parameters, see 3.8 IP RAN Redundancy. For details about board redundancy, port redundancy, and port load sharing, refers to RNC Parts

Reliability in the RNC Product Description

3.10 IP RAN DHCP The Dynamic Host Configuration Protocol (DHCP) dynamically provides configuration parameters for network terminals. The DHCP can automatically allocate the network address and set up the OM channel for IP RAN. The DHCP has the following characteristics: z

Working in the Client/Server mode. When receiving the request from a client, the server provides parameters such as the IP address, gateway address, DNS server address for the client.

z

Simplifying IP address management.

z

Enabling centralized IP address management.

z

Complying with RFC 2131 and RFC 2132.

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3 IP RAN Principles

In the DHCP procedure, the RNC works as the DHCP server and the NodeBs work as DHCP clients. The NodeB can automatically obtain the IP address to set up the OM channel. Figure 3-24 shows the DHCP procedure. Figure 3-24 DHCP procedure

The four basic phases of the DHCP procedure are as follows: Step 1 DHCP discovery: The NodeB broadcasts DHCPDISCOVER packets to find the RNC. Step 2 DHCP offer: The RNC sends the configuration information such as IP addresses to the NodeB through DHCPOFFER packets. Step 3 DHCP selection: The NodeB selects an IP address from the DHCPOFFER packets and then responds by broadcasting DHCPREQUEST packets. Step 4 DHCP acknowledgement: The RNC responds by sending DHCPACK packets to the NodeB. The parameters on the RNC side are as follows: z

The First Serial Number

z

The Second Serial Number NodeB IP_TRANS IP address NodeB ATM_TRANS IP address

z z

----End

3.11 IP RAN Transport Capabilities IP RAN Transport Capabilities provides information about the transport capabilities related to the IP RAN.

3.11.1 RNC IP Transport Capabilities Table 3-7 describes the IP transport capabilities at the RNC. Table 3-7 IP transport capabilities at the RNC

3-30

Item

Sub-Item

Description

Physical interfaces

Board

At most 14 per RBS and 10 per RSS

FE port

4 FEs per sub-board and 2 sub-boards per board


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3 IP RAN Principles

Item

Sub-Item

Description

GE port

1 GE per sub-board and 2 sub-boards per board

E1/T1

32 E1s/T1s per sub-board and 1 sub-board per board

IP version

IP protocol version

IPv4

Layer 2 protocols

MAC/FE or MAC/GE

Supported

PPP/E1

Supported

PPPmux/E1

Supported

ML PPP/E1

Supported

MC PPP/E1

Supported

PPP/E1/SDH

Supported

PPPmux/E1/SDH

Supported

ML PPP/E1/SDH

Supported

MC PPP/E1/SDH

Supported

PPP/SDH

Supported

PPPmux/SDH

Supported

QoS

DiffServ

Supported

Header compression

IP Header Compression over PPP (RFC 2507)

Supported (on E1)

Reliability

Port backup

Supported (FG2a/GOUa/POUa/UOIa inter-board level)

Board backup

Supported (all the interface boards)

NOTE: RBS = RNC Business Subrack, RSS = RNC Switch Subrack, IPv4 = Internet Protocol version 4, MAC = Media Access Control, PPPMux = PPP Multiplexing, ML PPP = Multi-Link PPP, MC PPP = Multi-Class PPP, SDH = Synchronous Digital Hierarchy, QoS = Quality of Service, DiffServ = Differentiated Services

3.11.2 BBU IP Transport Capabilities Table 3-8 describes the IP transport capabilities at the BBU. Table 3-8 IP transport capabilities at the BBU (DBS3800 and iDBS3800) Item

Quantity/Location

Flow

Protocol

E1/T1

8 per BBU

–

PPP

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3 IP RAN Principles

Item

Quantity/Location

Flow

Protocol

FE

2 per BBU

–

MAC

IPoA client

1 per BBU

–

ATM

Maintenance flow on the Iub interface

1 per BBU

Low

TCP

Traffic flow

Several per BBU

High

UDP

Signaling flow

Several per BBU

Medium

SCTP

IP route flow

Several per BBU

High

IP

NOTE: IPoA = IP over ATM, TCP = Transfer Control Protocol, UDP = User Datagram Protocol, SCTP = Stream Control Transmission Protocol

Table 3-9 describes the IP transport capabilities at the BBU (DBS3900 and iDBS3900). Table 3-9 IP transport capabilities abilities at the BBU (DBS3900 and iDBS3900) Item

Quantity/Location

Flow

Protocol

E1/T1

4 per WMPT, 8 per UTRP

–

PPP

FE

1 optical and 1 electrical per WMPT

–

MAC

IPoA client

1 per BBU

–

ATM


1 per BBU

Low

TCP

Traffic flow

Several per BBU

High

UDP

Signaling flow

Several per BBU

Medium

SCTP

IP route flow

Several per BBU

High

IP

NOTE: IPoA = IP over ATM, TCP = Transfer Control Protocol, UDP = User Datagram Protocol, SCTP = Stream Control Transmission Protocol

3.11.3 Macro NodeB IP Transport Capabilities Table 3-10 and Table 3-11show the IP transport capabilities at the macro NodeB. Table 3-10 IP transport capabilities at the macro NodeB (BTS3812E/BTS3812AE)

3-32

Item

Quantity/Location

Flow

Protocol

E1/T1

8 per interface board

–

PPP

FE


–

MAC


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3 IP RAN Principles

Item

Quantity/Location

Flow

Protocol

IPoA client

Several per interface board

–

ATM


1 per BBU

Low

TCP

Traffic flow


High

UDP

Signaling flow


Medium

SCTP

IP route flow

Several per interface board (inter-board flow supported)

High

IP

Table 3-11 IP transport capabilities at the macro NodeB (BTS3900/BTS900A) Item

Quantity/Location

Flow

Protocol

E1/T1

4 per WMPT, 8 per UTRP

–

PPP

FE

1 optical and 1 electrical per WMPT

–

MAC

IPoA client


–

ATM


1 per BBU

Low

TCP

Traffic flow


High

UDP

Signaling flow


Medium

SCTP

IP route flow

Several per interface board (inter-board flow supported)

High

IP

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4 IP RAN Parameters

4

IP RAN Parameters

This chapter provides information on the effective level and configuration of the parameters related to IP RAN. Table 4-1 lists the parameters related to IP RAN. Table 4-1 Parameters related to IP RAN Parameter Name

Parameter ID

Effective Level


TnlBearerType

NodeB(ADD NODEB)

RNC

IP Trans Apart Ind

IPTRANSAPARTI ND

NodeB(ADD NODEB)

RNC

Adjacent Node Type

NODET

Adjacent Node(ADD ADJNODE)

RNC

Transport Type

TRANST

Adjacent Node(ADD ADJNODE)

RNC

Bearing Mode

MODE

NodeB(SET E1T1BEAR)

NodeB

Local IP address

IPADDR

IP Path(ADD IPPATH)

RNC

Peer IP address

PEERIPADDR

IP Path(ADD IPPATH)

RNC

Peer subnet mask

PEERMASK

IP Path(ADD IPPATH)

RNC

IP path type

PATHT

IP Path(ADD IPPATH)

RNC

DSCP

DSCP

IP Path(ADD IPPATH)

RNC

Port Type

PT

IP Path(ADD IPPATH)

NodeB

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4 IP RAN Parameters

Parameter Name

Parameter ID

Effective Level

NodeB IP address

NODEBIP

IP Path(ADD IPPATH)

NodeB

RNC IP address

RNCIP

IP Path(ADD IPPATH)

NodeB

Traffic Type(ADD IPPATH)

TFT

IP Path(ADD IPPATH)

NodeB

Differentiated Services Code Point

DSCP

IP Path(ADD IPPATH)

NodeB

Signalling link mode

MODE

SCTP(ADD SCTPLNK)

RNC

First local IP address

LOCIPADDR1

SCTP(ADD SCTPLNK)

RNC

Second local IP address

LOCIPADDR2

SCTP(ADD SCTPLNK)

RNC

First destination IP address

PEERIPADDR1

SCTP(ADD SCTPLNK)

RNC

Second destination IP address

PEERIPADDR2

SCTP(ADD SCTPLNK)

RNC

Local SCTP port No.

LOCPTNO

SCTP(ADD SCTPLNK)

RNC

Destination SCTP port No.

PEERPORTNO

SCTP(ADD SCTPLNK)

RNC

SCTP link No.

SCTPLNKN

SCTP(ADD SCTPLNK) SCTP(ADD CCP)

Configuration on...

RNC

SCTP(ADD NCP)

4-2

NodeB(ADD NCP)

Bearing link type

CARRYLNKT

Local IP address

LOCIP

SCTP(ADD SCTPLNK)

NodeB

Second Local IP address

SECLOCIP

SCTP(ADD SCTPLNK)

NodeB

Peer IP address

PEERIPADDR

SCTP(ADD SCTPLNK)

NodeB

Second Peer IP address

SECPEERIP

SCTP(ADD SCTPLNK)

NodeB

Local SCTP Port

LOCPORT

SCTP(ADD SCTPLNK)

NodeB

NodeB(ADD CCP)


RNC

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4 IP RAN Parameters

Parameter Name

Parameter ID

Effective Level

Peer SCTP Port

PEERPORT

SCTP(ADD SCTPLNK)

NodeB

NCP/CCP Bearing Type

BEAR

IUBCP(ADD IUBCP)

NodeB

Local IP Address

IP

OMCH(ADD OMCH)

NodeB

Local IP Mask

MASK

OMCH(ADD OMCH)

NodeB

Peer IP address

PEERIP

OMCH(ADD OMCH)

NodeB

Peer IP Mask

PEERMASK

OMCH(ADD OMCH)

NodeB

Bear Type

BEAR

OMCH(ADD OMCH)

NodeB

Adjacent node ID

ANI

AAL2 Path(ADD AAL2PATH)

RNC

AAL2 path ID

PATHID


RNC

AAL2 path ID

PATHID


NodeB

Node Type

NT


NodeB

Path Type

PAT


NodeB

Interface type

SAALLNKT

SAAL(ADD SAALLNK)

RNC

Bearing VPI

CARRYVPI

SAAL(ADD SAALLNK)

RNC

Bearing VCI

CARRYVCI

SAAL(ADD SAALLNK)

RNC

SAAL link No.

SAALLNKN

SAAL(ADD SAALLNK) SAAL(ADD CCP)

Configuration on...

RNC

SAAL(ADD NCP) Bearing VPI

VPI

SAAL(ADD SAALLNK)

NodeB

Bearing VCI

VCI

SAAL(ADD SAALLNK)

NodeB

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4 IP RAN Parameters

Parameter Name

Parameter ID

Effective Level

Configuration on...

NCP/CCP Bearing Type

BEAR

IUBCP(ADD IUBCP)

NodeB

CN domain ID

CNDomainId

RNC(ADD CNNODE)

RNC

IU transfers bearer type

TnlBearerType

RNC(ADD CNNODE)

RNC

IUR trans bearer type

TnlBearerType

RNC(ADD NRNC)

RNC

Iur Interface Existing Indication

IurExistInd

RNC(ADD NRNC)

RNC

MLPPP type

MPTYPE

MLPPP Group, MLPPP Link(ADD MPGRP)

RNC

Multi Class PPP

MCPPP

MLPPP Group(ADD MPGRP)

NodeB

PPP Link(ADD PPPLNK)

PPP mux

PPPMUX

PPP MuxCP

MUXCP


NodeB

Destination IP address

DESTIP

IP Route(ADD IPRT)

RNC

Forward route address

NEXTHOP

IP Route(ADD IPRT)

RNC

Signal Priority

SIGPRI

NodeB(SET DIFPRI)

NodeB

OM priority

OMPRI

NodeB(SET DIFPRI)

NodeB

VLANID Flag

VLANFlAG

RNC

MLPPP Group, PPP Link(ADD MPGRP)

SCTP(ADD SCTPLNK)

RNC

IP Path(ADD IPPATH) RNC(ADD VLANID)

VLAN ID

VLANID

IP Path(ADD IPPATH)

RNC

SCTP(ADD SCTPLNK)

4-4

Vlan priority

VLANPRI

RNC(SET DSCPMAP)

RNC

Traffic Type

TRAFFIC

NodeB(SET VLANCLASS)

NodeB


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4 IP RAN Parameters

Parameter Name

Parameter ID

Effective Level

User Data Service Priority

SRVPRIO


NodeB

Insert VLAN Tag

INSTAG


NodeB

Vlan Id

VLANID


NodeB

Vlan priority

VLANPRIO


NodeB

FPMUX flag

FPMUX

IP Path(ADD IPPATH)

RNC

Max subframe length

SUBFRLEN

IP Path(ADD IPPATH)

RNC

Maximum Frame Length

MAXFRAMELEN

IP Path(ADD IPPATH)

RNC

FPTIME

FPTIME

IP Path(ADD IPPATH)

RNC

Head compress

IPHC

PPP Link(ADD PPPLNK) MLPPP Group，PPP Link(ADD MPGRP) MLPPP Group(ADD MPGRP)

Configuration on...

RNC

IP Header Compress

IPHC

Board type

BRDTYPE

Board(ADD BRD)

RNC

Backup

RED

Board(ADD BRD)

RNC

Port No.

PN

Ethernet port(ADD ETHREDPORT)

RNC

Gateway IP address

GATEWAY

Ethernet port (STR GATEWAYCHK)

RNC


BAKIP


RNC

Backup port mask

BAKMASK

Ethernet port(STR GATEWAYCHK)

RNC


BAKGATEWAY


RNC

Check type

CHKTYPE


RNC

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4 IP RAN Parameters

4-6

Parameter Name

Parameter ID

Effective Level

Port work mode

MODE


RNC

Min interval of BFD packet send

MINTXINT


RNC

Min interval of BFD packet receive

MINRXINT


RNC

detect multiplier of BFD packet

BFDDETECTCOU NT

Current BFD communication.(STR GATEWAYCHK)

RNC

The First Serial Number

NBLB1

RNC(ADD NODEBESN)

RNC

The Second Serial Number

NBLB2

RNC(ADD NODEBESN)

RNC

NodeB IP_TRANS IP address

NBIPOAMIP

RNC(ADD NODEBIP)

RNC

NodeB ATM_TRANS IP address

NBATMOAMIP

RNC(ADD NODEBIP)

RNC


Configuration on...

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5 IP RAN Reference Documents

5

IP RAN Reference Documents

IP RAN Reference Documents lists the references documents related to IP RAN. z

3GPP TR25.933: IP transport in UTRAN

z

3GPP TR23.107: Quality of Service (QoS) concept and architecture

z

RFC1661: The Point-to-Point Protocol (PPP), provides a standard method for transporting multi-protocol datagrams over point-to-point links

z

RFC1662: PPP in HDLC-link Framing, describes the use of HDLC-like framing for PPP encapsulated packets

z

RFC1990: The PPP Multilink Protocol (ML-PPP), describes a method for splitting, recombining and sequencing datagrams across multiple logical data links

z

RFC2686: The Multi-Class Extension to Multi-link PPP (MC-PPP), describes extensions that allow a sender to fragment the packets of various priorities into multiple classes of fragments, allowing high-priority packets to be sent between fragments of lower priorities

z

RFC3153: PPP Multiplexing (PPPmux), describes a method to reduce the PPP framing overhead used to transport small packets over low bandwidth links.

z

IETF RFC 1889(01/1996): RTP: A Transport Protocol for Real Time Applications

z

IETF DRAFT (02-2002): SS7 MTP3-User Adaptation Layer (M3UA)

z

IETF RFC 3309 (09/2002): Stream Control Transmission Protocol (SCTP) Checksum Change

z

IETF RFC2131: Dynamic Host Configuration Protocol

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IP RAN Description Issue 02 Date 2008-07-30 Huawei Proprietary and Confidential Copyright © Huawei Technologies Co

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