The QoS QoS solution solution in UMTS UMTS networks networks is developed by the following two phases: •
Elementary QoS control Figure shows shows the elementary QoS control solution! "n this solution# static basic QoS and subscriber definition information are stored in the $%&! 'efore the (olicy and )harging )ontrol *())+ architecture is introduced# only the 'S),&-) 'S),&-)## S.S-# $%&# and ..S- are used during the QoS negotiation at the network side! The QoS is seldom updated after the (acket /ata (rotocol *(/(+ conte0t is activated# and the session is provided with fi0ed QoS! Figure 1 Elementary QoS control solution
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1dvanced QoS control control Figure 2 shows 2 shows the advanced QoS control solution! 3n the basis of static QoS# the ()) architecture is introduced and the ()&F is a dded to store policy control information! 1fter the ()) ()) architecture is is introduced# the QoS QoS negotiation becomes becomes more fle0ible and various functions are available# for e0ample# time4 or location4based differentiated charging# data volume4based bandwidth control# and content4based differentiated differentiated operation! Figure 2 1dvanced 2 1dvanced QoS control control solution
Implementation Principles Principle for Elementary QoS Control Figure 5 shows 5 shows the QoS negotiation procedure in a typical UMTS network!
Figure 3 QoS negotiation procedure in a typical UMTS network
46: 7hen the user e8uipment *UE+ of a subscriber attaches to the network# the $%& inserts the QoS information subscribed by the subscriber into the subscriber data and delivers the subscriber data to the S.S-! 9: The UE sends an 1ctivate (/( )onte0t &e8uest message carrying the re8uested QoS information to the S.S-! The UE can also set the QoS parameter to 0 but does not provide the specific QoS re8uirement in the 1ctivate (/( )onte0t &e8uest message! The value 0 indicates that the UE uses the default QoS on the $%&! "n this case# the UE can use only non4real4time services! : The S.S- checks the QoS subscribed by the subscriber to determine whether the subscriber is allowed to apply for the relevant QoS profile! •
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"f the subscriber has subscribed to the QoS profile on the $%& and the S.S- has sufficient resources# the S.S- sends a )reate (/( )onte0t &e8uest message to the ..S-! "f the bandwidth and load resources of the S.S- are insufficient# the S.S- restricts the QoS profile and reduces the QoS or re;ects the 1ctivate (/( )onte0t &e8uest message!
•
"f the subscriber has n ot subscribed to the QoS profile on the $%&# the S.S- performs either of the following operations based on data configuration:
)onsiders the subscription information as invalid and re;ects the 1ctivate (/( )onte0t &e8uest message! Uses the S.S-
=: 1fter the ..S- receives a )reate (/( )onte0t &e8uest message# the ..S- ad;usts the QoS based on its own resources and includes the negotiated QoS in a )reate (/( )onte0t &esponse message and sends the message to the S.S-! Then# a .(&S Tunneling (rotocol *.T(+ tunnel is established between the ..S- and the S.S-! >: The S.S- notifies the &-) of the ne gotiated QoS and re8uests the &-) to establish a radio access bearer *&1'+! ?: The UT&1- where the &-) resides performs internal access control and resource reservation! •
"f the UT&1- has sufficient resources# the &-) sends a successful &adio 1ccess 'earer 1ssignment &esponse to notify the S.S- that the &1' is established!
"f the UT&1- resources are insufficient# the &-) sends a failed &adio 1ccess 'earer 1ssignment &esponse to notify the S.S- that the re8uested QoS cannot be provided! 1fter the S.S- receives such a response# it decreases the QoS attribute based on the result contained in the response and applies for &1' establishment again! The number of &1' re4establishment attempts and the QoS value for each &1' re4establishment re8uest can be configured! @: 1fter the &1' is established# the S.S- includes the negotiated QoS in an 1ctivate (/( )onte0t 1ccept message sent to the UE! The UE then determines whether to use services! •
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"f the UE accepts the negotiated QoS# the (/( conte0t that meets relevant QoS re8uirements is established between the UE and the ..S-! "f the UE cannot accept the negotiated QoS# it initiates the (/( conte0t deactivation procedure!
Principle for Advanced QoS Control 1s the ()) architecture *as shown in Figure 6+ is introduced# the ()&F is added and the negotiation between the ..S- and the ()&F *as sho wn in Figure 9+ is also added to the QoS negotiation procedure! The ()&F updates (/( conte0ts or service QoS according to service control re8uirements! The QoS parameters used over the .0 interface are different from the QoS parameters used in the typical UMTS network! The ..S- implements the mapping between these two sets of QoS p arameters!
Figure ()) architecture
Figure 9 shows the QoS negotiation procedure in the ()) architecture!
Figure ! QoS negotiation procedure in the ()) architecture
)ompared with the QoS negotiation procedure in the typical UMTS network# the QoS negotiation procedure in the ()) architecture is added with the QoS negotiation between the ..S- and the ()&F during (/( conte0t activation# as shown in steps =4> in Figure 9! The specific QoS negotiation between the ..S- and the ()&F is as follows: The ..S- negotiates with the ()&F on the QoS based on the value of the upgrade QoS Supported parameter in the )reate (/( )onte0t &e8uest message sent from the S.S-! •
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"f the upgrade QoS Supported parameter is not carried# the ..S- does not include this parameter in a ))& message sent to the ()&F either! The ()&F considers that the QoS upgrade is not supported by default and includes a low4level QoS in a ))1 message sent to the ..S-! The ..S- also includes a low4level QoS in a )reate (/( )onte0t &esponse message sent to the S.S-! "f the upgrade QoS Supported parameter is 1# the S.S- supports the QoS upgrade! The ..S- includes the QoS4Upgrade attribute4value pair *1A(+ with the value set to QoS"#P$%A&E"S#PP'%(E& in a ))& message sent to the ()&F! The ()&F includes a high4level QoS in a ))1 message sent to the ..S-! The ..S- also includes a high4level QoS in a )reate (/( )onte0t &esponse message sent to the S.S-!
"f the upgrade QoS Supported parameter is 0# the S.S- does not support the QoS upgrade! The ..S- includes the QoS4Upgrade 1A( with the value set to QoS"#P$%A&E")'("S#PP'%(E& in a ))& message sent to the ()&F! The ()&F includes a low4level QoS in a ))1 message sent to the ..S-! The ..S- also includes a low4 level QoS in a )reate (/( )onte0t &esponse message sent to the S.S-! The following section describes the QoS negotiation procedure in the following scenarios: •
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QoS establishment when a subscriber goes online *))&4"nitial+
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..S-4initiated QoS update *))&4Update+
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()&F4initiated QoS delivery *&1&+
QoS Esta*lis+ment ,+en a Su*scri*er $oes 'nline -CC%.Initial/ )'(E For details about the procedure in which a subscriber goes online# see "(4)1- Session Establishment! 7hen a subscriber goes online# the ..S- sends a ))&4"nitial message carrying the QoS4-egotiation and QoS4Upgrade 1A(s to the ()&F! The ()&F sends a ))14"nitial message# in which the QoS4 "nformation varies depending on the settings of the QoS4-egotiation and QoS4Upgrade 1A(s: •
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"f the QoS negotiation is not supported# the ()&F delivers the QoS re8uested by the policy and charging enforcement function *()EF+! For e0ample# if the ()EF re8uests the QoS of 6 Mbit,s and the QoS of 2 Mbit,s is configured on the ()&F# the ()&F delivers the QoS of 6 Mbit,s! "f the QoS upgrade is not supported# the QoS delivered by the ()&F cannot be greater than the QoS re8uested by the ()EF! For e0ample# if the ()EF re8uests the QoS of 2 Mbit,s and the QoS of 6 Mbit,s is configured on the ()&F# the ()&F delivers the QoS of 2 Mbit,s!
"f the QoS4-egotiation 1A( is not carried in the ))&4"nitial message# the QoS negotiation is supported by default! "f the QoS4Upgrade 1A( is not carried in the ))&4"nitial message# the QoS upgrade is not supported by default! The U()) generates the authoriBed QoS per bearer after implementing the negotiation and upgrade of the QoS per bearer based on the re8uested QoS per bearer and the configured QoS policies! Then# the U()) processes the parameters of the QoS per service flow based on the authoriBed QoS per bearer to ensure that the QoS per service flow is not greater than the authoriBed QoS per bearer! 1s defined in the protocol# the QoS class identifier *Q)"+ of the QoS per service flow must be consistent with the Q)" of the authoriBed QoS per bearer! The U()) replaces the QoS per service flow with the QoS per bearer when the QoS per service flow is greater than the QoS per b earer! )'(E •
For details about the QoS pe r bearer and the QoS per service flow# see .04interface QoS!
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The QoS per service flow cannot be greater than the authoriBed QoS per bearer!
$$S).Initiated QoS #pdate -CC%.#pdate/ )'(E For details about the ..S-4initiated QoS update procedure# see UE4"nitiated "(4)1- Session Update! 7hen a QoS policy needs to update# the ..S- sends a ))&4Update message carrying the QoS4 -egotiation and QoS4Upgrade 1A(s to the ()&F! The ()&F sends a ))14Update message# in which the QoS4"nformation varies depending on the settings of the QoS4-egotiation and QoS4Upgrade 1A(s: •
"f the QoS negotiation is not supported# the ()&F delivers the QoS re8uested by the ()EF! For e0ample# if the ()EF re8uests the QoS of 6 Mbit,s and the QoS of 2 Mbit,s is configured on the ()&F# the ()&F delivers the QoS of 6 Mbit,s!
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"f the QoS upgrade is not supported# the QoS delivered by the ()&F cannot be greater than the QoS re8uested by the ()EF! For e0ample# if the ()EF re8uests the QoS of 2 Mbit,s and the QoS of 6 Mbit,s is configured on the ()&F# the ()&F delivers the QoS of 2 Mbit,s!
"f the QoS4-egotiation 1A( is not carried in the ))&4Update message# the QoS negotiation is supported by default! "f the QoS4Upgrade 1A( is not carried in the ))&4Update message# the ()&F performs subse8uent operations based on the value of the QoS4Upgrade 1A( carried in the previous ))& message! )'(E 1s defined in the protocol# the value of the QoS4-egotiation 1A( is valid only to the current message whereas the value of the QoS4Upgrade 1A( is inherited between messages e0changed over a bearer! The QoS per service flow cannot be greater than the a uthoriBed QoS per bearer# but the Q)"s of the two levels of QoS must be consistent! The U()) replaces the QoS per service flow with the QoS per bearer when the QoS per service flow is greater than the QoS per bearer! )'(E •
For details about the QoS pe r bearer and the QoS per service flow# see .04interface QoS!
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The QoS per service flow cannot be greater than the authoriBed QoS per bearer!
PC%F.Initiated QoS &elivery -%A%/ )'(E For details about the ()&F4initiated QoS delivery procedure# see ()&F4"nitiated "(4)1- Session Update! 7hen the ()&F proactively delivers new QoS policies to the ..S-# it sends an &1& message! The QoS4"nformation carried in the &1& message is independent of the QoS4-egotiation and QoS4Upgrade 1A(s! The QoS per service flow cannot be greater than the a uthoriBed QoS per bearer# but the Q)"s of the two levels of QoS must be consistent! The U()) replaces the QoS per service flow with the QoS per bearer when the QoS per service flow is greater than the QoS per bearer! For details about the QoS per bearer and the QoS per service flow# see .04interface QoS! %eference apping et,een QCIs and #(S QoS Parameters The QoS negotiated between the ..S- and the ()&F is called authoriBed QoS! The QoS information includes the Q)" and data rates *M'& and .'&+! For details about QoS over the .0 interface# see QoS4 related 1A(s! The Q)" is calculated by using the QoS parameters over the .n interface! The QoS parameters consist of traffic class *T)+# traffic handle p riority *T$(+# signaling indication *S"+# and source statistics descriptor *SS/+! Table lists the mapping between Q)"s and QoS parameters! (a*le 1 Mapping between Q)"s and UMTS QoS parameters
QCI
#(S QoS Parameter (C
(P
SI
SS&
)onversational
n,a
n,a
speech
2
)onversational
n,a
n,a
unknown
(a*le 1 Mapping between Q)"s and UMTS QoS parameters
QCI
#(S QoS Parameter (C
(P
SI
SS&
5
2 Streaming
n,a
n,a
speech
6
2 Streaming
n,a
n,a
unknown
9
5 "nteractive
Ces
n,a
5 "nteractive
-o
n,a
=
5 "nteractive
2
-o
n,a
>
5 "nteractive
5
-o
n,a
?
6 'ackground
n,a
n,a
n,a
)'(E The concepts mentioned in the above table are described as follows: •
•
•
•
•
•
Q)" is short for QoS class identifier! "t is a QoS attribute in the evolved packet core *E()+ network that specifies the QoS level of packet forwarding behaviors *such as packet loss rate and delay+# which is provided for service data flows *S/Fs+! The packet forwarding behaviors are implemented based on Q)"s that are predefined on the access network node# such as the e-ode'! T) is short for traffic class! There are four types of traffic in the UMTS network: conversational# streaming# interactive# and background! T$( is short for traffic handle priority! "t indicates the relative importance of a ll S/Us belonging to a bearer compared with all S/Us of other bearers! S" is short for signaling indication! "t indicates whether submitted S/Us are transmitted over signaling links! SS/ is short for source statistics descriptor! "t describes the characteristic of the data source from which S/Us are sent! S/U is short for service data unit! "t is a unit of data transmitted between neighboring layers of the protocol stack!
Concepts The ()&F interworks with the ()EF over the .0 interface! For details about the .0 interface# see 7$F/4@@@ (olicy )ontrol over the .0 "nterface Using /iameter /escription! Parent topic QoS in UMTS -etworks
