3GPP TS 29.207 V5.6.0 (2003-12)
`
`Technical Specification
`
`3rd Generation Partnership Project;
`Technical Specification Group Core Network;
`Policy control over Go interface
`(Release 5)
`
`
`
`
`
`The present document has been developed within the 3rd Generation Partnership Project (3GPP TM) and may be further elaborated for the purposes of 3GPP.
`
`
`The present document has not been subject to any approval process by the 3GPP Organizational Partners and shall not be implemented.
`
`This Specification is provided for future development work within 3GPP only. The Organizational Partners accept no liability for any use of this Specification.
`Specifications and reports for implementation of the 3GPP TM system should be obtained via the 3GPP Organizational Partners' Publications Offices.
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`T-MOBILE EXHIBIT 1105
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`Release 5
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`3GPP TS 29.207 V5.6.0 (2003-12)
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`Keywords
`UMTS, performance
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`
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`3GPP
`
`Postal address
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`
`3GPP support office address
`650 Route des Lucioles - Sophia Antipolis
`Valbonne - FRANCE
`Tel.: +33 4 92 94 42 00 Fax: +33 4 93 65 47 16
`
`Internet
`http://www.3gpp.org
`
`Copyright Notification
`
`No part may be reproduced except as authorized by written permission.
`The copyright and the foregoing restriction extend to reproduction in all media.
`
`© 2003, 3GPP Organizational Partners (ARIB, CCSA, ETSI, T1, TTA, TTC).
`All rights reserved.
`
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`3GPP
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`Contents
`
`Foreword............................................................................................................................................................. 5
`1
`Scope ........................................................................................................................................................ 6
`2
`References ................................................................................................................................................ 6
`3
`Definitions and abbreviations ................................................................................................................... 7
`3.1 Definitions ............................................................................................................................................................... 7
`3.2 Abbreviations .......................................................................................................................................................... 8
`4
`Go interface .............................................................................................................................................. 9
`4.1 Overview ................................................................................................................................................................. 9
`4.2 Go reference model ............................................................................................................................................... 11
`4.3
`Functional elements and capabilities ..................................................................................................................... 11
`4.3.1
`GGSN .............................................................................................................................................................. 11
`4.3.1.1
`Service-based local policy enforcement point ................................................................................................. 11
`4.3.1.1.1
`QoS Information processing ....................................................................................................................... 12
`4.3.1.2
`Initialisation and maintenance ......................................................................................................................... 13
`4.3.1.3 Gate function ................................................................................................................................................... 13
`4.3.1.4 Void 13
`4.3.1.5 Binding mechanism handling .......................................................................................................................... 13
`4.3.2
`PDF .................................................................................................................................................................. 14
`4.3.2.1
`Service-based local policy decision point ........................................................................................................ 14
`4.3.2.2
`Initialisation and maintenance ......................................................................................................................... 15
`4.3.2.3 Binding mechanism handling .......................................................................................................................... 15
`5
`Policy control procedures ....................................................................................................................... 16
`5.1 GGSN .................................................................................................................................................................... 16
`5.1.1
`Initial authorization at PDP context activation ................................................................................................ 16
`5.1.2
`Modification of previously authorized PDP context ........................................................................................ 16
`5.1.3
`Session modification initiated decision............................................................................................................ 17
`5.1.4
`PDP context deactivation ................................................................................................................................. 17
`5.1.5
`Gate control operation ..................................................................................................................................... 18
`5.1.6
`User plane operation ........................................................................................................................................ 18
`5.2
`PDF........................................................................................................................................................................ 18
`5.2.1
`SBLP decisions ................................................................................................................................................ 18
`5.2.1.1
`SBLP authorisation decision ............................................................................................................................ 18
`5.2.1.2
`Session modification initiated decision............................................................................................................ 20
`5.2.1.3
`SBLP revoke decision ...................................................................................................................................... 20
`5.2.1.4
`SBLP gate decision .......................................................................................................................................... 21
`5.2.2
`Support for forking .......................................................................................................................................... 21
`5.2.2.1 Authorization of resources for forked responses ............................................................................................. 21
`5.2.2.2 Updating the authorization information at the final answer ............................................................................. 21
`6
`Go protocol ............................................................................................................................................. 22
`6.1
`Protocol support .................................................................................................................................................... 22
`6.1.1
`TCP connection for COPS protocol ................................................................................................................. 22
`6.1.2
`COPS protocol ................................................................................................................................................. 22
`6.2 Basic COPS events/messages ................................................................................................................................ 23
`6.2.1
`Type of messages ............................................................................................................................................. 23
`6.3 Go events/messages ............................................................................................................................................... 23
`6.3.1
`Event descriptions ............................................................................................................................................ 23
`6.3.1.1 Common Header, Client Type ......................................................................................................................... 23
`6.3.1.2 Context Object ................................................................................................................................................. 23
`6.3.1.3 Client Specific Information (ClientSI) for outsourcing Operation .................................................................. 24
`6.3.1.4 Conformance Section ....................................................................................................................................... 24
`6.3.1.5 Reporting of Device Capabilities and Device Limitations............................................................................... 25
`6.3.1.6
`Initial Go Policy Provisioning ......................................................................................................................... 26
`6.3.2
`Message description ......................................................................................................................................... 26
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`6.4 Go data .................................................................................................................................................................. 29
`6.5
`Security Considerations ......................................................................................................................................... 29
`
`Annex A:
`
`(Void) ..................................................................................................................................... 30
`
`Annex B (normative):
`
`3GPP Go PIB.................................................................................................. 31
`
`Flow identifiers: Format definition and examples ...................................... 50
`Annex C (normative):
`C.1 Format of a flow identifier ..................................................................................................................... 50
`C.2 Example 1 ............................................................................................................................................... 50
`C.3 Example 2 ............................................................................................................................................... 51
`
`Annex D (normative):
`
`Go interface related error code values for the PDP context handling ...... 53
`
`Annex E (informative):
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`Overview of the 3GPP Go PIB working mode ............................................ 54
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`Annex F (informative):
`
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`Change history ............................................................................................... 56
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`Foreword
`This Technical Specification has been produced by the 3rd Generation Partnership Project (3GPP).
`
`The contents of the present document are subject to continuing work within the TSG and may change following formal
`TSG approval. Should the TSG modify the contents of the present document, it will be re-released by the TSG with an
`identifying change of release date and an increase in version number as follows:
`
`Version x.y.z
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`where:
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`x
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`the first digit:
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`1 presented to TSG for information;
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`2 presented to TSG for approval;
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`3 or greater indicates TSG approved document under change control.
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`y
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`the second digit is incremented for all changes of substance, i.e. technical enhancements, corrections,
`updates, etc.
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`z
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`the third digit is incremented when editorial only changes have been incorporated in the document.
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`Scope
`1
`The present document provides the stage 3 specification of the Go interface. The functional requirements and the
`stage 2 specifications of the Go interface are contained in 3GPP TS 23.002 [2] and 3GPP TS 23.207 [3]. The Go
`interface is the interface between the GGSN and the Policy Decision Function (PDF).
`
`The present document defines:
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`the protocol to be used between PDF and GGSN over the Go interface;
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`the signalling interactions to be performed between PDF and GGSN over the Go interface;
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`the information to be exchanged between PDF and GGSN over the Go interface.
`
`References
`2
`The following documents contain provisions which, through reference in this text, constitute provisions of the present
`document.
`
` References are either specific (identified by date of publication and/or edition number or version number) or
`non-specific.
`
` For a specific reference, subsequent revisions do not apply.
`
` For a non-specific reference, the latest version applies. In the case of a reference to a 3GPP document (including
`a GSM document), a non-specific reference implicitly refers to the latest version of that document in the same
`Release as the present document.
`
`[1]
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`[2]
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`[3]
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`[4]
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`[5]
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`[6]
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`[7]
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`[8]
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`[9]
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`[10]
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`[11]
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`[12]
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`[13]
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`[14]
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`[15]
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`[16]
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`[17]
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`[18]
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`3GPP TR 21.905: "Vocabulary for 3GPP Specifications".
`
`3GPP TS 23.002: "Network architecture".
`
`3GPP TS 23.207: "End-to-end Quality of Service (QoS) concept and architecture".
`
`3GPP TS 23.228: "IP Multimedia Subsystem (IMS); Stage 2".
`
`Void.
`
`IETF RFC 2753: "A Framework for Policy-based Admission Control".
`
`IETF RFC 2748: "The COPS (Common Open Policy Service) Protocol".
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`IETF RFC 3084: "COPS Usage for Policy Provisioning (COPS-PR)".
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`IETF RFC 3159: "Structure of Policy Provisioning Information (SPPI)".
`
`Void.
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`IETF RFC 3520: "Session Authorization Policy Element".
`
`3GPP TS 24.008: "Mobile radio interface Layer 3 specification; Core network protocols; Stage 3".
`
`3GPP TS 27.060: "Packet domain; Mobile Station (MS) supporting Packet Switched services".
`
`3GPP TS 24.229: "IP Multimedia Call Control Protocol based on SIP and SDP; Stage 3".
`
`IETF RFC 3318: "Framework Policy Information Base".
`
`IETF RFC 3289: "Management Information Base for the Differentiated Services Architecture"
`
`IETF RFC 2327: "SDP: Session Description Protocol".
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`3GPP TS 29.208: "End-to-end Quality of Service (QoS) signalling flows".
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`[19]
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`[20]
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`[21]
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`[22]
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`IETF RFC 3291: "Textual Conventions for Internet Network Addresses".
`
`3GPP TS 29.060: "General Packet Radio Service (GPRS); GPRS Tunnelling Protocol (GTP)
`across the Gn and Gp interface".
`
`3GPP TS 32.225: "Telecommunication management; Charging management; Charging data
`description for the IP Multimedia Subsystem (IMS)".
`
`IETF RFC 3313: "Private Session Initiation Protocol (SIP) Extensions for Media Authorization"
`
`3
`
`Definitions and abbreviations
`
`3.1
`
`Definitions
`
`For the purposes of the present document, the terms and definitions given in 3GPP TR 21.905 [1] and the following
`apply:
`
`Authorization Token: consists of the IMS session identifier and the PDF identifier in conformance with RFC 3520
`[11]. It is used for authorizing the QoS for the IP flow (s). The UE includes an authorization token as part of the binding
`information in order to obtain QoS authorization for the IMS session. The UE obtains this authorization token via SIP
`from the P-CSCF by means of an extension SIP header described in RFC 3313 [22]. The P-CSCF communicates with
`the PDF in order to obtain a suitable authorization token for the UE.
`
`Binding Information: consists of an authorization token and the flow identifier(s) of IP flow(s) carried by a PDP
`context. When receiving an authorization token, the UE includes binding information when activating or modifying a
`PDP context. It is used for authorizing the QoS of the IP flows carried within a PDP context and to verify that the
`grouping of the IP flows is correct.
`
`Client Handle: an object in the COPS messages used as a unique number to correlate all the COPS messages with the
`same dialogue. Over the Go interface the Client Handle is used to correlate COPS messages with respect to the same
`PDP Context. For the exact definition see RFC 2748 [7] and RFC 3084 [8].
`
`Common Open Policy Service (COPS) protocol: is a simple query and response protocol that can be used to
`exchange policy information between a policy server (Policy Decision Point) and its clients (Policy Enforcement
`Points)
`
`Flow identifier: used for the identification of the IP flows, described within a media component associated with a SIP
`session. A Flow identifier consists of two parts: 1) the ordinal number of the position of the "m=" lines in the SDP (RFC
`2327 [17]) session description and 2) the ordinal number of the IP flow(s) within the “m=” line assigned in the order of
`increasing port numbers. Examples are provided in Annex C.
`
`Go Interface: interface between PDF and GGSN (3GPP TS 23.002 [2])
`
`GPRS Charging ID (GCID): the Charging Id generated by the GGSN as defined in 3GPP TS 29.060 [20].
`
`IP Bearer Service Manager: uses standard IP mechanisms to manage the IP Bearer Service. It resides in the GGSN
`and optionally in the UE.
`
`IP flow: a unidirectional flow of IP packets with the same source IP address and port number and the same destination
`IP address and port number and the same transport protocol. Port numbers are only applicable if used by the transport
`protocol.
`
`Media component: is a part of an SDP session description conveying information about media (e.g. media type,
`format, IP address, port(s), transport protocol, bandwidth, direction).
`
`The media described by a media component can be either bi- or unidirectional. Media using RTP for transport may also
`have associated RTCP If so, the media component also conveys information about the associated RTCP (port and
`possibly bandwidth). An SDP session description can consist of more than one media component. A media component
`shall not be deleted nor its position changed within the SDP session description. A media component line where the port
`number has previously been set to 0 may be reused for a new media component.
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`Policy Decision Function (PDF): is a logical policy decision element that uses standard IP mechanisms to implement
`policy in the IP media layer
`The PDF makes decisions in regard to network based IP policy using policy rules, and communicates these decisions to
`the PEP in the GGSN.
`
`Proxy Call Session Control Function (P-CSCF): is a network element providing session management services
`(e.g. telephony call control)
`
`Policy Enforcement Point (PEP): is a logical entity that enforces policy decisions made by the PDF. It resides in the
`IP BS Manager of the GGSN
`
`Policy Information Base (PIB): is a set of policy data carried by COPS-PR
`The protocol assumes a named data structure, known as a Policy Information Base (PIB), to identify the type and
`purpose of solicited and unsolicited policy information that is sent from the Policy Decision Point to the Policy
`Enforcement Point for provisioning policy or sent from the Policy Enforcement Point to the Policy Decision Point as a
`notification.
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`Provisioning Instance Identifier (PRID): uniquely identifies an instance of a PRC
`
`QoS class: identifies a bearer service (which is associated with a set of bearer service characteristics)
`
`Translation/mapping function: provides the inter-working between the mechanisms and parameters used within the
`UMTS Bearer Service and those used within the IP Bearer Service
`
`UMTS Bearer Service Manager: handles resource reservation requests from the UE. It resides in the GGSN and the
`UE
`
`3.2
`
`Abbreviations
`
`For the purposes of the present document, the abbreviations given in 3GPP TR 21.905 [1] and the following apply:
`
`COPS
`COPS-PR
`DEC
`DRQ
`GCID
`ICID
`IMS
`MIB
`P-CSCF
`PDF
`PEP
`PIB
`PRC
`PRI
`PRID
`QoS
`REQ
`RPT
`RTCP
`SBLP
`SDP
`
`Common Open Policy Service protocol
`COPS for policy PRovisioning
`COPS DECision message
`COPS Delete ReQuest state message
`GPRS Charging IDentifier
`IM CN Subsystem Charging IDentifier
`IP Multimedia core network Subsystem
`Management Information Base
`Proxy Call Session Control Function
`Policy Decision Function
`Policy Enforcement Point
`Policy Information Base
`PRovisioning Class (a type of policy data)
`PRovisioning Instance (an instance of a PRC)
`PRovisioning Instance iDentifier
`Quality of Service
`COPS REQuest message
`COPS RePorT state message
`RTP Control Protocol
`Service Based Local Policy
`Session Description Protocol
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`Go interface
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`4.1
`
`Overview
`
`The Go interface allows service-based local policy information to be "pushed" to or requested by the Policy
`Enforcement Point (PEP) in the GGSN from a Policy Decision Function (PDF). As defined in the stage 2 specifications
`3GPP TS 23.207 [3], this information is used by the GGSN for:
`
`- GPRS bearer authorisation;
`
`- Charging correlation;
`
`- Policy based "gating" function in GGSN;
`
`The Go interface uses IP flow based policies.
`
`The Common Open Policy Service (COPS) protocol has been developed as a protocol for use between a policy server
`and a network device, as described in RFC 2748 [7].
`
`In addition, COPS for Provisioning extensions have been developed as described in RFC 3084 [8] with RFC 3159 [9]
`describing a structure for specifying policy information that can then be transmitted to a network device for the purpose
`of configuring policy at that device. The model underlying this structure is one of well-defined provisioning classes and
`instances of these classes residing in a virtual information store called the Policy Information Base (PIB).
`
`The Go interface shall conform to the IETF COPS (RFC 2748 [7]) and the extensions of COPS-PR (RFC 3084 [8]). For
`the purpose of exchanging the required specific Go information, a 3GPP Go COPS-PR Policy Information Base (PIB) is
`defined in the present document.
`
`COPS Usage for Policy Provisioning (COPS-PR) is independent of the type of policy being provisioned (QoS, Security,
`etc.). In the present document, COPS-PR is used to communicate service-based local policy information between PDF
`and GGSN. COPS-PR can be extended to provide per-flow policy control along with a 3GPP Go Policy Information
`Base (PIB). The 3GPP Go PIB may inherit part of the data object definitions from other PIBs and MIBs defined in the
`IETF.
`
`Signalling flows related to the Go interface are specified in 3GPP TS 29.208 [18].
`
`The minimum functionalities that the Go interface shall cover are introduced below.
`
`1. Media Authorisation request from GGSN:
`
` The GGSN receives the binding information during the activation of a (Secondary) PDP context or during the
`modification of an existing PDP context that has been previously authorized by the PDF. To authorise the
`PDP context activation, the GGSN shall send a media authorisation request to the PDF. To authorise the PDP
`context modification, the GGSN shall send a media authorisation request to the PDF when the requested QoS
`exceeds the authorised QoS or new binding information is received.
`
` This authorisation request shall include the following information:
`
`- Binding information:
`
` The binding information is used by the GGSN to identify the correct PDF and subsequently request
`service-based local policy information from the PDF. The GGSN may receive one or more sets of the
`binding information during an activation or modification of a PDP context. Each binding information
`consists of:
`
`- One Authorisation token;
`
`- One or more Flow identifiers within the session.
`
`
`
`It is assumed that only one set of binding information is carried within a PDP context in this Release.
`
`2. Media authorisation decision from PDF:
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` The media authorisation information sent by the PDF to the GGSN, contains at a minimum the following
`information:
`
`- Decision on the binding information.
`
` The PDF shall respond with an authorisation decision for the binding information. The authorisation decision
`shall identify that the binding information is validated with an ongoing SIP session. Additionally, the PDF shall
`verify if the IP flows of the multiple media components are correctly assigned to the PDP Context. If validated,
`the PDF shall also communicate the following media authorisation details to the GGSN:
`
`-
`
`"Authorised QoS".
`
` This information is used by the GGSN to authorise the media resources according to the service-based
`local policy and the requested bearer QoS.
`
` The "Authorised QoS" signalled over the Go interface is based on the SDP requirements signalled and
`agreed previously within SIP signalling for this session.
`
` The "Authorised QoS" specifies the maximum QoS that is authorised for a PDP context for that specific
`binding information. In case of an aggregation of multiple media components within one PDP context, the
`combination of the "Authorised QoS" information of the individual IP flows of the media components is
`provided as the "Authorised QoS" for the bearer.
`
` The "Authorised QoS" contains the following information:
`
`- QoS class:
`
` The QoS class information represents the highest class that can be used for the media component. It is
`derived from the SDP media description. The QoS class within the "Authorized QoS" information for
`the bearer is determined from the QoS class values of the individual IP flows of these media
`components identified in the binding information.
`
`- Data rate:
`
` The Data rate information is derived from the SDP bandwidth parameters. The Data rate shall include
`all the overhead coming from the IP-layer and the layers above, e.g. UDP, RTP or RTCP. If multiple
`codecs are agreed to be used in a session, the authorized data rate is set according to the codec
`requiring the highest bandwidth, meaning that terminals may under use the authorized data rate when
`choosing to use another agreed codec. The Data rate within the "Authorized QoS" information for the
`bearer is determined from the data rate values of the individual IP flows identified in the binding
`information.
`
`- Packet Classifier.
`
` The packet classifier for media components is based on the IP-address and port number information in the
`SDP and shall allow for all IP flows associated with the SDP media component description.
`
`3. Charging correlation:
`
` The PDF shall send the ICID (see 3GPP TS 24.229 [14]) provided by the P-CSCF as part of the authorisation
`decision. The GGSN shall send the GCID (see 3GPP TS 29.060 [20]) of the PDP Context and the GGSN address
`to the PDF as part of the authorisation report.
`
`4. Approval of QoS Commit / Removal of QoS Commit / Revoke Authorisation for GPRS and IP resources:
`
` The PDF controls media components and may revoke resources at any time. Approval of QoS Commit /
`Removal of QoS Commit / Revoke Authorisation for GPRS and IP resources is communicated by the PDF to the
`GGSN.
`
`5. Indication of PDP Context Release / Modification to/from 0 kbit/s:
`
` The GGSN informs the PDF of bearer changes related to the authorised resources for the IMS session in the
`following cases:
`
`- Loss of radio contact (modification to/from 0 kbit/s for conversational and streaming class);
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`- Deactivation of PDP context.
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`4.2
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`Go reference model
`
`The Go interface is defined between the PDF and the GGSN (3GPP TS 23.002 [2]).
`
`The PDF is a logical entity of the P-CSCF (if the PDF is implemented in a separate physical node, the interface between
`the PDF and P-CSCF is not standardised).
`
`The P-CSCF (PDF) is in the same PLMN as the GGSN.
`
`The relationships between the different functional entities involved are depicted in figure 4.2.
`
`SIP/SDP Signalling
`
`P-CSCF
`
`Go
`
`PDF
`
`(Policy Decision Function)
`
`GGSN
`
`
`
`PEP
`(Policy Enforcement Point)
`
`UE
`
`SIP Client
`
`
`
`Signalling path
`
`
`
`IP BS Manager
`
`IP BS Manager
`
` Translation/mapping
`function
`
` Translation/mapping
`function
`
`
`
`UMTS BS Manager
`
`
`
`UMTS BS Manager
`
`NOTE:
`
`For clarity in the diagram, network elements that are not involved in service-based local policy are not
`presented here (e.g. radio network elements, SGSN, etc).
`
`
`
`Figure 4.2: Go interface architecture model
`
`4.3
`
`Functional elements and capabilities
`
`4.3.1 GGSN
`
`4.3.1.1
`
`Service-based local policy enforcement point
`
`The Policy Enforcement Point (PEP) is a logical entity which resides in the GGSN and communicates with the PDF
`regarding Service-based local policy (SBLP) control. Hereafter in the present document, the GGSN is assumed to
`contain the PEP implicitly unless otherwise stated. The GGSN sends requests to and receives decisions from the PDF.
`The GGSN may cache the policy decision data of the PDF decisions. This cached information may be used later for a
`local policy decision allowing the GGSN to make policy control decision about the QoS authorization for PDP context
`modifications without requiring additional interaction with the PDF in case the modification request does not exceed the
`previously authorized QoS.
`
`The following policy enforcement point functionalities for SBLP in the GGSN are identified:
`
`- Policy based Authorisation:
`
` The GGSN requests authorisation information from the PDF for the IP flows carried by a PDP context. The
`GGSN enforces the PDF decisions for this PDP context.
`
`The GGSN shall enforce unsolicited authorisation decisions which update the QoS and packet classifiers.
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`Additionally, policy-based authorisation ensures that the resources, which can be used by the PDP context
`are within the "Authorised QoS" specified by the PDF. This information is mapped by the
`Translation/mapping function in the GGSN to give the authorised resources for GPRS bearer admission
`control.
`
` The GGSN shall also report to the PDF its success or failure in carrying out the PDF decision.
`
`- Policy based gating functionality:
`
`
`
`Policy based gating functionality represent the control of the GGSN over the Gate Function in the user plane,
`i.e. the forwarding of IP packets associated with a media component. In the user plane, a "gate" is defined for
`each IP flow of a media component. The PDF provides the gate description and the commands to open or
`close the gate. The gate description is received from the PDF in the authorisation decision. The command to
`open or close the gate shall be sent either in the authorisation decision or in subsequent decisions from the
`PDF.
`
`-
`
`Indication of bearer release/modification to/from 0 kb/s:
`
` The GGSN shall inform the PDF when the bearer changes to or from a data rate of 0 kb/s (an indication of
`bearer loss/recovery), and at bearer release.
`
`- Charging Correlation
`
` To ensure charging correlation, the PEP shall send the GCID and the GGSN address to the PDF. The PDF
`shall also send the IMS charging identifier to the GGSN.
`
`4.3.1.1.1 QoS Information processing
`
`The GGSN is responsible for the policy based authorisation, i.e. to ensure that the requested QoS is in-line with the
`"Authorized QoS".
`
`The GGSN needs the "Authorised QoS" information of the PDP context for the uplink as well as for the downlink
`direction. Therefore, the "Authorized QoS" information for the combination of all IP flows of each direction associated
`with the media component as determined by the PDF is used.
`
`In case of an aggregation of multiple media components within one PDP context, the "Authorised QoS" for the bearer is
`provided by the PDF as the combination of the "Authorised QoS" information of the individual media components.
`
`The GGSN shall perform the proper mapping betw