1、 Reference number ISO/IEC 23916:2005(E) ISO/IEC 2005INTERNATIONAL STANDARD ISO/IEC 23916 First edition 2005-11-01Information technology Telecommunications and information exchange between systems Corporate Telecommunication Networks Signalling Interworking between QSIG and SIP Call Transfer Technolo
2、gies de linformation Tlcommunications et change dinformation entre systmes Rseaux de tlcommunications dentreprise Interaction de signalisation entre QSIG et SIP Transfert dappel ISO/IEC 23916:2005(E) PDF disclaimer This PDF file may contain embedded typefaces. In accordance with Adobes licensing pol
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7、1 11 Fax + 41 22 749 09 47 E-mail copyrightiso.org Web www.iso.org Published in Switzerland ii ISO/IEC 2005 All rights reservedISO/IEC 23916:2005(E) ISO/IEC 2005 All rights reserved iiiContents Page Foreword .v Introductionvi 1 Scope1 2 Normative references1 3 Terminology.2 4 Definitions3 4.1 Extern
8、al definitions .3 4.2 Other definitions3 4.2.1 User A .3 4.2.2 User B .3 4.2.3 User C .3 4.2.4 Call transfer3 4.2.5 Single step call transfer4 4.2.6 Call transfer by join.4 4.2.7 Call transfer by rerouteing .4 4.2.8 Corporate telecommunication Network (CN)4 4.2.9 IP network4 4.2.10 Private Integrate
9、d Services Network (PISN) .4 4.2.11 Private Integrated services Network eXchange (PINX) .4 5 Abbreviations and acronyms .4 6 Background and architecture 5 7 Procedures.5 7.1 Call transfers in QSIG .5 7.2 Call transfer in SIP.6 7.3 Scope of the interworking functions.6 7.3.1 QSIG side.6 7.3.2 SIP sid
10、e.6 7.3.3 Discussion over transfer interworking functions 6 7.4 Mapping of numbers and URIs 9 7.5 UAC Processing 10 7.5.1 Receipt of a FACILITY message with callTransferComplete invoke APDU 10 7.5.2 Receipt of a FACILITY message with callTransferUpdate invoke APDU.10 7.5.3 Receipt of a FACILITY mess
11、age with ssctInitiate invoke APDU.10 7.5.4 Receipt of a SETUP message with ssctSetup invoke APDU 11 7.5.5 Receipt of a FACILITY message with subaddressTransfer invoke APDU.12 7.6 UAS Processing.12 7.6.1 Receipt of a SIP REFER request 12 7.6.2 Receipt of a SIP INVITE request.17 7.6.3 Receipt of a SIP
12、 request with revised identity .18 8 Example message sequences19 8.1 Call transfer by join where User B and C are SIP participants.19 8.2 Call transfer where User A is a SIP participant 20 8.3 Call transfer where User A is a SIP participant and where two gateways are used.21 8.4 Call transfer where
13、User A and User B are SIP participants.22 8.5 Single step call transfer where User B is a SIP participant 23 8.6 Unsuccessful Single step call transfer where User A and User C are SIP participants 24 8.7 Single step call transfer where User A and User B are SIP participants.25 9 Security considerati
14、ons . 25ISO/IEC 23916:2005(E) iv ISO/IEC 2005 All rights reservedForeword ISO (the International Organization for Standardization) and IEC (the International Electrotechnical Commission) form the specialized system for worldwide standardization. National bodies that are members of ISO or IEC partici
15、pate in the development of International Standards through technical committees established by the respective organization to deal with particular fields of technical activity. ISO and IEC technical committees collaborate in fields of mutual interest. Other international organizations, governmental
16、and non-governmental, in liaison with ISO and IEC, also take part in the work. In the field of information technology, ISO and IEC have established a joint technical committee, ISO/IEC JTC 1. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. Th
17、e main task of the joint technical committee is to prepare International Standards. Draft International Standards adopted by the joint technical committee are circulated to national bodies for voting. Publication as an International Standard requires approval by at least 75 % of the national bodies
18、casting a vote. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO and IEC shall not be held responsible for identifying any or all such patent rights. ISO/IEC 23916 was prepared by Ecma International (as ECMA 361) and was adopte
19、d, under a special “fast- track procedure”, by Joint Technical Committee ISO/IEC JTC 1, Information technology, in parallel with its approval by national bodies of ISO and IEC. ISO/IEC 23916:2005(E) ISO/IEC 2005 All rights reserved v Introduction This International Standard is one of a series of Sta
20、ndards defining the interworking of services and signalling protocols deployed in corporate telecommunication networks (CNs) (also known as enterprise networks). The series uses telecommunication concepts as developed by ITU-T and conforms to the framework of International Standards on Open Systems
21、Interconnection as defined by ISO/IEC. This International Standard specifies call transfer interworking between the Session Initiation Protocol (SIP) and QSIG within corporate telecommunication networks (also known as enterprise networks). SIP is an Internet application-layer control (signalling) pr
22、otocol for creating, modifying, and terminating sessions with one or more participants. These sessions include, in particular, telephone calls. This International Standard is based upon the practical experience of member companies and the results of their active and continuous participation in the w
23、ork of ISO/IEC JTC1, ITU-T, IETF, ETSI and other international and national standardization bodies. It represents a pragmatic and widely based consensus. INTERNATIONAL STANDARD ISO/IEC 23916:2005(E) ISO/IEC 2005 All rights reserved 1 Information technology Telecommunications and information exchange
24、 between systems Corporate Telecommunication Networks Signalling Interworking between QSIG and SIP Call Transfer 1 Scope This International Standard specifies call transfer interworking between the Session Initiation Protocol (SIP) and “QSIG” within corporate telecommunication networks (CN), also kn
25、own as enterprise networks. “QSIG“ is a signalling protocol that operates between Private Integrated services Network eXchanges (PINX) within a Private Integrated Services Network (PISN). A PISN provides circuit-switched basic services and supplementary services to its users. QSIG is specified in St
26、andards, in particular 1 (call control in support of basic services), 2 (generic functional protocol for the support of supplementary services) and a number of Standards specifying individual supplementary services. Transfer services are specified in 3, 6 and the QSIG signalling protocol in support
27、of these services is specified in 4, 7. In particular, this signalling protocol signals information about call transfer to the users who are involved. NOTE The name QSIG was derived from the fact that it is used for signalling at the Q reference point. The Q reference point is a point of demarcation
28、 between two PINXs. SIP is an application layer protocol for establishing, terminating and modifying multimedia sessions. It is typically carried over IP. Telephone calls are considered as a type of multimedia session where just audio is exchanged. SIP is defined in 10. As the support of telephony w
29、ithin corporate networks evolves from circuit-switched technology to Internet technology, the two technologies will co-exist in many networks for a period, perhaps several years. Therefore there is a need to be able to establish, modify, terminate and transfer sessions involving participants in the
30、SIP network and participants in the QSIG network. Such calls are supported by gateways that perform interworking between SIP and QSIG. This specification specifies SIP-QSIG signalling interworking for transfer services between a PISN employing QSIG and a corporate IP network employing SIP. 2 Normati
31、ve references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. 1 International Standard ISO/IEC 11
32、572 “Information technology - Telecommunications and information exchange between systems - Private Integrated Services Network - Circuit mode bearer services - Inter- exchange signalling procedures and protocol“ (also published by Ecma as Standard ECMA-143). 2 International Standard ISO/IEC 11582 “
33、Information technology - Telecommunications and information exchange between systems - Private Integrated Services Network - Generic functional protocol for the support of supplementary services - Inter-exchange signalling procedures and protocol “ (also published by Ecma as Standard ECMA-165). ISO/
34、IEC 23916:2005(E) 2 ISO/IEC 2005 All rights reserved 3 International Standard ISO/IEC 13865 “Information technology - Telecommunications and information exchange between systems - Private Integrated Services Network - Specification, functional model and information flows - Call Transfer supplementar
35、y service“ (also published by Ecma as Standard ECMA-177). 4 International Standard ISO/IEC 13869 “Information technology - Telecommunications and information exchange between systems - Private Integrated Services Network - Inter-exchange signalling protocol - Call Transfer supplementary service“ (al
36、so published by Ecma as Standard ECMA-178). 5 International Standard ISO/IEC 17343 “Information technology - Telecommunications and information exchange between systems - Corporate telecommunication networks - Signalling interworking between QSIG and SIP - Basic services“ (also published by Ecma as
37、Standard ECMA-339). 6 International Standard ISO/IEC 19459 “Information technology - Telecommunications and information exchange between systems - Private Integrated Services Network - Specification, functional model and information flows - Single Step Call Transfer Supplementary Service“ (also publ
38、ished by Ecma as Standard ECMA-299). 7 International Standard ISO/IEC 19460 “Information technology - Telecommunications and information exchange between systems - Private Integrated Services Network - Inter-exchange signalling protocol - Single Step Call Transfer supplementary service“ (also publis
39、hed by Ecma as Standard ECMA-300). 8 Ecma Technical Report TR/86, “Corporate Telecommunication Networks User Identification in a SIP/QSIG Environment“. 9 Bradner, S., “Key words for use in RFCs to Indicate Requirement Levels“, BCP 14, RFC 2119. 10 J. Rosenberg, H. Schulzrinne, et al., “SIP: Session
40、initiation protocol“, RFC 3261. 11 J. Peterson, “A Privacy Mechanism for the Session Initiation Protocol (SIP)“, RFC 3323. 12 R. Sparks, “The Session Initiation Protocol (SIP) REFER Method“, RFC 3515. 13 R. Mahy, B. Biggs, R. Dean, “The Session Initiation Protocol (SIP) “Replaces“ Header“, RFC 3891.
41、 14 R. Sparks, “The Session Initiation Protocol (SIP) Referred-By Mechanism“, RFC 3892. 15 R. Sparks, A. Johnston, “Session Initiation Protocol Call Control - Transfer“, draft-ietf-sipping-cc-transfer- 02 (work in progress). 3 Terminology In this document, the key words “MUST“, “MUST NOT“, “REQUIRED
42、“, “SHALL“, “SHALL NOT“, “SHOULD“, “SHOULD NOT“, “RECOMMENDED“, “MAY“, and “OPTIONAL“ are to be interpreted as described in RFC 2119 9 and indicate requirement levels for compliant SIP implementations. In the interests of keeping the normative text and the diagrams as simple as possible, the QSIG me
43、ssages in this document implicitly follow QSIG signalling rules of 1 and 2. For instance, sending a QSIG DISCONNECT message on a call where a QSIG DISCONNECT has already been sent is implicitly forbidden and therefore not mentioned as such in this document. The figures in this document are provided
44、as examples. They are not normative. In the interests of keeping the diagrams simple, some SIP messages (ACK, PRACK, final responses to BYE and NOTIFY) are not shown. The following notation is used for call transfer information within QSIG messages: xxx.inv - invoke application protocol data unit (A
45、PDU) of operation xxx. ISO/IEC 23916:2005(E) ISO/IEC 2005 All rights reserved 3 xxx.res - return result APDU of operation xxx. xxx.err - return error APDU of operation xxx. The following abbreviations are used: ctActive stands for callTransferActive. ctComplete stands for callTransferComplete. The d
46、rawings use the following conventions: D1 and D2 are SIP dialogs. CR1 and CR2 are QSIG call references. By convention, D1 is mapped to CR1 and D2 to CR2. A SIP message is prefixed by (Dx-y), when it belongs to SIP dialog Dx and is part of SIP transaction y. The method or response code of the SIP mes
47、sages is displayed, as well as the name of SIP header fields that play a role in the interworking functions. Some examples display an “Identity:“ information field. It indicates that the local identity information field should be mapped to a real SIP identity information field as described in 7.4. 4
48、 Definitions For the purposes of this specification, the following definitions apply. 4.1 External definitions The definitions in 1 and 10 apply as appropriate. 4.2 Other definitions 4.2.1 User A the served user, i.e. the user requesting Call transfer or Single step call transfer. 4.2.2 User B a use
49、r who is in communication with User A and who will be transferred to User C. NOTE This definitions differs from 3, in order to use similar conventions for QSIG Call transfer and QSIG Single step call transfer. 4.2.3 User C the user to whom the call is transferred. 4.2.4 Call transfer the act of enabling a user (User A) to transform two of that users calls (at least one of which must be answered) in
