1、 TIA DOCUMENT All-IP Core Network Multimedia Domain IP Multimedia Subsystem Accounting Information Flows and Protocol TIA-873.008 DECEMBER 2003 TELECOMMUNICATIONS INDUSTRY ASSOCIATION The Telecommunications Industry Association represents the communications sector of Copyright Telecommunications Ind
2、ustry Association Provided by IHS under license with EIANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NOTICE TIA Engineering Standards and Publications are designed to serve the public interest through eliminating misunderstandings between manufacturers and purch
3、asers, facilitating interchangeability and improvement of products, and assisting the purchaser in selecting and obtaining with minimum delay the proper product for their particular need. The existence of such Publications shall not in any respect preclude any member or non-member of TIA from manufa
4、cturing or selling products not conforming to such Publications. Neither shall the existence of such Documents preclude their voluntary use by non-TIA members, either domestically or internationally. TIA DOCUMENTS TIA Documents contain information deemed to be of technical value to the industry, and
5、 are published at the request of the originating Committee without necessarily following the rigorous public review and resolution of comments which is a procedural part of the development of a American National Standard (ANS). Further details of the development process are available in the TIA Engi
6、neering Manual, located at http:/www.tiaonline.org/standards/sfg/engineering_manual.cfm TIA Documents shall be reviewed on a five year cycle by the formulating Committee and a decision made on whether to reaffirm, revise, withdraw, or proceed to develop an American National Standard on this subject.
7、 Suggestions for revision should be directed to: Standards CWTS China Wireless Telecommunications Standards group, 4 China; ETSI European Telecommunications Standards Institute; ATIS, USA; TTA - Telecommunications 5 Technology Association, Korea; and TTC Telecommunication Technology Committee, Japan
8、), which 6 have granted license for reproduction and for use by 3GPP2 and its Organizational Partners. 7 8 9 Revision History 10 11 Revision Changes Date 0 Initial Publication December 2003 12 13 Copyright Telecommunications Industry Association Provided by IHS under license with EIANot for ResaleNo
9、 reproduction or networking permitted without license from IHS-,-,-TIA-873-008 1 1 Scope 1 The present document covers offline charging for the IMS. For clarity, the terms Offline Charging and Online 2 charging as applied to the IMS are defined here in clause 3. These definitions are the same as lis
10、ted in 2. 3 The IMS charging architecture details, requirements, definitions and principles are listed in 2 and therefore 4 are not repeated here. 5 In the present document the charging data triggers, message content and format are specified along with the 6 transport of these messages using the Dia
11、meter protocol. Details about charging message flows and the 7 definitions of the Diameter AVPs are also included in the present document. This information is divided into 8 two main clauses: Online Charging and Offline Charging. 9 2 References 10 The following documents contain provisions, which th
12、rough reference in this text, constitute provisions of the 11 present document. 12 References are either specific (identified by date of publication, edition number, version number, etc.) 13 or non-specific. 14 For a specific reference, subsequent revisions do not apply. 15 For a non-specific refere
13、nce, the latest version applies. In the case of a reference to a 3GPP2 document 16 a non-specific reference implicitly refers to the latest version of that document in the same Release as 17 the present document. 18 1 Void 19 2 3GPP2 X.S0013-007: “IP Multimedia Subsystem, Charging Architecture” 20 T
14、IA-873-007: “IP Multimedia Subsystem, Charging Architecture” 21 3 IETF RFC 3588: “Diameter Base Protocol“ 22 4 3GPP2 S.S0086-0: “3GPP2 IMS Security Framework” 23 5 3GPP2 X.S0013-003: “IP Multimedia (IM) session handling; IM call model; Stage 2“ 24 TIA-873-003: “IP Multimedia (IM) session handling; I
15、M call model; Stage 2“ 25 6 IETF RFC 2486: “The Network Access Identifier“ 26 7 3GPP2 X.S0011-C: “cdma20001Wireless IP Network Standard” 27 TIA -835-C: “cdma2000 Wireless IP Network Standard” 28 8 Void 29 9 ITU-T Recommendation X.690: “Information technology - ASN.1 encoding rules: Specification of
16、30 Basic Encoding Rules (BER), Canonical Encoding Rules (CER) and Distinguished Encoding Rules 31 (DER)“ 32 1cdma2000 is the trademark for the technical nomenclature for certain specifications and standards of the Organizational Partners (OPs) of 3GPP2. When applied to goods and services, the cdma20
17、00mark certifies their compliance with cdma2000standards. Geographically (and as of the date of publication), cdma2000 is a registered trademark of the Telecommunications Industry Association (TIA-USA) in the United States. Copyright Telecommunications Industry Association Provided by IHS under lice
18、nse with EIANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-TIA-873-008 2 10 ITU-T Recommendation X.691: “Information technology - ASN.1 encoding rules: Specification of 1 Packed Encoding Rules (PER)“ 2 11 ITU-T Recommendation X.693: “Information Technology - ASN.1
19、 encoding rules: XML encoding 3 Rules (XER)“ 4 12 Void 5 13 Void 6 14 3GPP2 X.S0013-004: “IP Multimedia Call Control Protocol based on SIP and SDP; Stage 3“ 7 TIA-873-004: “IP Multimedia Call Control Protocol based on SIP and SDP; Stage 3“ 8 15 IETF RFC 3455: “Private Extensions to the Session Initi
20、ation Protocol (SIP) for the 3rdGeneration 9 Partnership Projects (3GPP)“ 10 16 IETF RFC 3261: “SIP: Session Initiation Protocol“ 11 17 IETF RFC 2327: “SDP: Session Description Protocol“ 12 17a IETF RFC 3266: “Support for IPv6 in Session Description Protocol“ 13 18 3GPP2 X.S0013-002: “IP Multimedia
21、Subsystem (IMS); Stage 2“ 14 TIA -873-002: “IP Multimedia Subsystem (IMS); Stage 2“ 15 19 3GPP2 X.S0013-006: “Cx Interface based on the Diameter protocol; Protocol Details“ 16 TIA -873-006: “Cx Interface based on the Diameter protocol; Protocol Details“ 17 3 Definitions, symbols and abbreviations 18
22、 3.1 Definitions 19 For the purposes of the present document, the following terms and definitions apply: 20 offline charging: charging mechanism where charging information does not affect, in real-time, the service 21 rendered 22 online charging: charging mechanism where charging information can aff
23、ect, in real-time, the service 23 rendered and therefore a direct interaction of the charging mechanism with session/service control is required 24 3.2 Symbols 25 For the purposes of the present document, the following symbols apply: 26 Rb Online Charging Reference Point between Session Charging Fun
24、ction and Correlation 27 Function 28 Rc Online Charging Reference Point between ECF and Correlation Function 29 Re Online Charging Reference Point towards a Rating Server 30 Rf Offline Charging Reference Point between an IMS Network Entity or an AS and AAA 31 Ro Online Charging Reference Point betwe
25、en an AS or MRFC and the ECF 32 3.3 Abbreviations 33 For the purposes of the present document, the abbreviations defined in 2 and the following apply: 34 AAA Authentication, Authorization, and Accounting 35 ABNF Augmented Backus-Naur Form36 Copyright Telecommunications Industry Association Provided
26、by IHS under license with EIANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-TIA-873-008 3 ACA Accounting-Answer 1 ACR Accounting-Request 2 AIR Accounting Information Record 3 ANM Answer Message 4 AS Application Server 5 ASA Abort-Session-Answer 6 ASR Abort-Session
27、-Request 7 AVP Attribute Value Pair 8 B2BUA Back-to-Back User Agent 9 BGCF Breakout Gateway Control Function 10 BS Billing System 11 CSCF Call Session Control Function (I-Interrogating; P-Proxy; and S-Serving) 12 ECF Event Charging Function 13 ECUR Event Charging with Unit Reservation 14 IAM Initial
28、 Address Message 15 ICN-BCP IP Connectivity Network Bearer Control Point 16 IEC Immediate Event Charging 17 IMS IP Multimedia Subsystem 18 ISC IMS Service Control 19 MGCF Media Gateway Control Function 20 MRFC Media Resource Function Controller 21 MRFP Multimedia Resource Function Processor 22 OCS O
29、nline Charging System 23 REL Release Message 24 SCCF Subscriber Content Charging Function 25 SDP Session Description Protocol 26 SIP Session Initiation Protocol 27 UE User Equipment 28 UUS-Data User to User Data 29 4 Offline and Online Charging 30 4.1 Implementation of Offline and Online Charging 31
30、 The IMS charging architecture, described in 2, specifies that for offline charging all communications between 32 the IMS network entities and the AAA are carried out on the Rf interface. On the other hand, for online 33 charging the Ro interface is used by the AS and MRFC towards the Event Charging
31、 Function and the ISC 34 interface is used between the S-CSCF and the Session Charging Function. The rules governing the selection of 35 the proper interfaces are described in the subclauses below. 36 4.1.1 Usage of Rf and Ro Interfaces 37 The AS and MRFC are able to distinguish whether to apply off
32、line or online charging, i.e. whether to send 38 charging information on the Rf interface to the AAA or on the Ro interface to the ECF (or to use both). The 39 decision of which interface to use is based on the information (AAA and/or ECF address) the AS/MRFC 40 receive in the SIP signaling and the
33、system configuration as provisioned by the operator. If the AS/MRFC only 41 receive the AAA address and do not receive an ECF address then they use only the Rf interface. If only the 42 ECF address was provided then they use only the Ro interface. In cases where both AAA and ECF addresses 43 are pro
34、vided it is possible to use both interfaces simultaneously. 44 However, operators may overrule the addresses received via the SIP signalling and use their own configured 45 rules instead. Operators may configure locally on the AS/MRFC an ECF and/or AAA address. The AAA 46 address may be locally conf
35、igured on all other IMS nodes. The choice of whether the IMS nodes use the 47 locally configured addresses or the addresses received by SIP signalling, and the decision on which interface(s) 48 to use, is left for operator configuration. 49 Copyright Telecommunications Industry Association Provided
36、by IHS under license with EIANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-TIA-873-008 4 4.1.2 Usage of Rf and ISC Interfaces 1 All other IMS nodes (S-CSCF, P-CSCF, I-CSCF, BGCF and MGCF) apply offline charging via the Rf 2 interface using the AAA address as rece
37、ived via SIP signaling or the locally configured AAA address. The S-3 CSCF supports online charging using the ISC interface, i.e. if the application server addressed over ISC is the 4 Session Charging Function of the OCS. 5 4.2 Diameter Protocol Basic Principles and Use 6 The present document define
38、s an IMS charging Diameter application, which utilizes the Diameter Base 7 Protocol 3. This application is used for both online and offline charging. The generic description of the 8 protocol is provided in the subclauses below while the portions of the protocol application associated with 9 offline
39、 and online charging are described in clauses 5 and 6, respectively. 10 4.2.1 Basic Principles 11 The IMS charging Diameter application is based on the following general principles: 12 The basic functionality of Diameter, as defined by the Diameter Base Protocol 3 is re-used in IMS. 13 For offline c
40、harging IMS network elements report accounting information to the Authentication, 14 Authorization, and Accounting Entity (AAA). The AAA uses this information to construct and format 15 AIRs. 16 For online charging, the AS and MRFC in the IMS network report credit control information to the 17 Event
41、 Charging Function (ECF). The ECF uses this information to support the event based charging 18 (content charging) function of the OCS. 19 4.2.2 Application Requirement for the Base Protocol 20 4.2.2.1 Offline Specific Base Protocol Requirements 21 In order to support the offline charging principles
42、described in the present document, the Diameter client and 22 server must implement at least the following Diameter options listed in 3: 23 To send/receive Abort-Session-Request. 24 To send/receive Abort-Session-Answer. 25 All other options of the Diameter Base Protocol are beyond the scope of the p
43、resent document. 26 A configurable timer is supported in the AAA to supervise the reception of the ACR Interim and/or ACR 27 Stop. An instance of the Timer is started at the beginning of the accounting session, reset on the receipt of 28 an ACR Interim and stopped at the reception of the ACR Stop. U
44、pon expiration of the timer, the AAA stops 29 the accounting session with the appropriate error indication. For Offline Charging, the client implements the 30 state machine described in 3. The server (AAA) implements the STATELESS ACCOUNTING state machine 31 as specified in 3, i.e. there is no order
45、 in which the server expects to receive the accounting information. 32 4.2.2.2 Online Specific Base Protocol Requirements 33 Specific support for online charging is not provided in this version of this specification. 34 4.2.2.3 Security Considerations 35 Diameter security is addressed in the base pr
46、otocol 3. Network security is specified in 4. 36 Copyright Telecommunications Industry Association Provided by IHS under license with EIANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-TIA-873-008 5 5 Offline Charging 1 5.1 Diameter Description on the Rf Interfaces
47、 2 5.1.1 Basic Principles 3 The offline charging functionality is based on the IMS network nodes reporting accounting information upon 4 reception of various SIP methods or ISUP messages, as most of the accounting relevant information is 5 contained in these messages. This reporting is achieved by s
48、ending Diameter Accounting-Requests (ACR) 6 Start, Interim, Stop and Event from the IMS nodes to the AAA. 7 The Diameter client uses ACR Start, Interim and Stop in procedures related to successful SIP sessions. It uses 8 ACR Events for unsuccessful SIP sessions and for session-unrelated procedures.
49、Further details are specified in 9 the tables below and in subclause 5.1.2. 10 It is operator configurable in the nodes for which SIP method or ISUP messages an Accounting-Request is sent, 11 with the exception that if accounting information is collected for sessions the ACR Start and ACR Stop 12 messages are mandatory according to the tables below. Tab
