ECMA TR 86-2003 Corporate Telecommunication Networks User Identification in a SIP QSIG Environment《企业电信网络 SIP QSIG环境中的用户识别》.pdf

1、 ECMA TR/86 1stEdition / December 2003 Corporate Telecommunication Networks User Identification in a SIP/QSIG Environment Technical Report ECMA TR/86 1stEdition / December 2003 Corporate Telecommunication Networks User Identification in a SIP/QSIG Environment Ecma International Rue du Rhne 114 CH-12

2、04 Geneva T/F: +41 22 849 6000/01 www.ecma-international.org IW TR-086.doc 06.01.2004 14:49 . Brief history This Technical Report investigates user identification within Corporate telecommunication Networks (CNs) (also known as enterprise networks) comprising a mixture of Private Integrated Services

3、 Network (PISNs) and Internet Protocol (IP) networks. It focuses on similarities and differences between numbers used in PISNs and Universal Resource Identifiers (URIs) used in IP networks, in particular where the Session Initiation Protocol (SIP) is used. This Technical Report is based upon the pra

4、ctical experience of Ecma member companies and the results of their active and continuous participation in the work of ISO/IEC JTC1, ITU-T, ETSI, IETF and other international and national standardization bodies. It represents a pragmatic and widely based consensus. The December 2003 General Assembly

5、 adopted this, 1stedition, of ECMA TR/86. Table of contents 1 Scope 1 2 References 1 3 Definitions 2 3.1 External definitions 2 3.2 Other definitions 2 3.2.1 Corporate telecommunication Network (CN) (also known as enterprise network) 2 3.2.2 Gateway 2 3.2.3 Identifier 2 3.2.4 Identification domain 2

6、 3.2.5 Identification number 2 3.2.6 IP network 2 3.2.7 Number 2 3.2.8 Numbering domain 2 3.2.9 PISN number 2 3.2.10 Privacy 2 3.2.11 Private Integrated Service Network (PISN) 2 3.2.12 Selection number 2 3.2.13 SIP network 2 3.2.14 Sub-domain 2 3.2.15 Trust domain 3 4 Acronyms 3 5 Background 3 6 Nam

7、ing schemes 4 6.1 The meaning of a name 4 6.2 Names and users 4 6.3 Numeric and non-numeric names 4 6.4 Context of a name 4 6.5 Allocation of names 4 6.6 Naming schemes in circuit-switched networks 4 6.7 Naming schemes in IP networks 5 6.8 Universal Communications Identifier (UCI) 5 7 Signalling pro

8、tocols 6 - i - 8 Overview of naming, numbering and addressing in QSIG 6 8.1 Numbers as a means of identifying entities 6 8.2 Numbering plans 7 8.3 Use of numbers in QSIG 7 9 Overview of identification in SIP 8 9.1 URIs as a means of identifying entities 8 9.1.1 Telephone URI 8 9.1.2 SIP URI 8 9.1.3

9、Display name 9 9.2 Use of URIs in SIP 9 10 Comparison of numbers and non-numeric names for use in SIP 10 10.1 Numbers in SIP 10 10.2 Non-numeric names in SIP 10 10.3 Summary 11 11 Interworking scenarios 11 12 Interworking functions 12 12.1 Converting PISN numbers to URIs 12 12.1.1 Selection and iden

10、tification numbers 12 12.1.2 Choice of URI scheme 12 12.1.3 Choice of host 12 12.1.4 Mapping the number to a URI userinfo field 12 12.2 Converting URIs to PISN numbers 13 12.2.1 Selection and identification numbers 13 12.2.2 Support of different URI schemes 13 12.2.3 Use of the host field 13 12.2.4

11、Mapping the URI userinfo field to a PISN number 13 13 Use of ENUM 13 14 Asserted identity and privacy in SIP 14 14.1 Overview of asserted identity RFC 14 14.2 Overview of general privacy RFC 14 14.3 Applicability to QSIG-SIP interworking 15 14.3.1 Trust within a CN 15 14.3.2 Trust outside a CN 16 15

12、 Conclusions 16 Annex A - Mapping between QSIG information elements and SIP P-Asserted-Identity and Privacy headers 17 - ii - 1 Scope This Technical Report examines means of identifying or naming users of telephony services within a Corporate telecommunication Network (CN) (also known as an enterpri

13、se network). Numeric names (numbers) are used in traditional Private Integrated Services Networks (PISNs) using QSIG as the network signalling protocol. They are also used for external communication, e.g., with a public Integrated Services Digital Network (ISDN). Names need not be numeric in Interne

14、t Protocol (IP) networks employing signalling protocols such as the Session Initiation Protocol (SIP). This Technical Report therefore looks at naming schemes that are appropriate within corporate IP networks, in particular corporate IP networks employing SIP as the signalling protocol. It also inve

15、stigates naming schemes that are appropriate in a mixed QSIG/SIP CN and the treatment of names at an interworking point. It details the use of names not only for selecting a user to participate in a call, but also as a means of identifying a user in a call to other users in that call. ENUM and priva

16、te ENUM-like services are also examined. 2 References ECMA-143 Private Integrated Services Network (PISN) - Circuit Mode Bearer Services - Inter-Exchange Signalling Procedures and Protocol (2001) ECMA-155 Private Integrated Services Networks - Addressing (1997) ECMA-164 Private Integrated Services N

17、etwork (PISN) - Inter-Exchange Signalling Protocol - Name Identification Supplementary Services (2001) ECMA-165 Private Integrated Services Network (PISN) - Generic Functional Protocol for the Support of Supplementary Services - Inter-Exchange Signalling Procedures and Protocol (2001) ETSI EG 201 94

18、0 Human Factors (HF); User identification solutions in converging networks (2001-04) ETSI TR 101 326 Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON); The procedure for determining IP addresses for routeing packets on interconnected IP networks that support public teleph

19、ony (2002-02) IETF RFC 1034 Domain Names Concepts and Facilities (1987-11) IETF RFC 2396 Uniform Resource Identifiers (URI): Generic Syntax (1998-08) IETF RFC 2806 URLs for Telephone Calls (1998-08) IETF RFC 2916 E.164 number and DNS (2000-09) IETF RFC 3261 SIP: Session Initiation Protocol (2002-06)

20、 IETF RFC 3323 A Privacy Mechanism for the Session Initiation Protocol (SIP) (2002-11) IETF RFC 3324 Short Term Requirements for Network Asserted Identity (2002-11) IETF RFC 3325 Private Extensions to the Session Initiation Protocol (SIP) for Asserted Identity within Trusted Networks (2002-11) ITU-T

21、 Recommendation E.164 The International Public Telecommunication Numbering Plan (1997-05) ITU-T Recommendation H.323 Packet-Based Multimedia Communications Systems (2000-11) - 1 - 3 Definitions For the purposes of this Technical Report, the following definitions apply. 3.1 External definitions This

22、Technical Report uses the following terms defined in other documents: Universal Resource Identifier (URI) (RFC 2396) Additionally the definitions in ECMA-143 and RFC 3261 apply as appropriate. 3.2 Other definitions 3.2.1 Corporate telecommunication Network (CN) (also known as enterprise network) Set

23、s of privately-owned or carrier-provided equipment that are located at geographically dispersed locations and are interconnected to provide telecommunication services to a defined group of users. NOTE A CN can comprise a PISN, a private IP network (intranet) or a combination of the two. 3.2.2 Gatewa

24、y A point of interworking between a PISN employing QSIG and a SIP network. 3.2.3 Identifier A name by which the user of a network is known. 3.2.4 Identification domain A set of identifiers controlled by a single administration. 3.2.5 Identification number A number used to identify an existing party

25、in a call (e.g., the calling party). 3.2.6 IP network A network, unless otherwise stated a CN, offering connectionless packet-mode services based on the Internet Protocol (IP) as the network layer protocol. 3.2.7 Number An identifier comprising a numeric string. 3.2.8 Numbering domain An identificat

26、ion domain in which identifiers are numbers. 3.2.9 PISN number A number identifying an entity in a PISN. 3.2.10 Privacy The withholding of a users identity from other users in a call in compliance with the wishes of that user. 3.2.11 Private Integrated Service Network (PISN) A private switched circu

27、it network. 3.2.12 Selection number A number used as the basis for routing a call to a destination (i.e., identifying the intended party in a call). 3.2.13 SIP network An IP network using SIP for the establishment of communication sessions (calls). 3.2.14 Sub-domain Part of a numbering domain in whi

28、ch all numbers share the same leading digits. - 2 - 3.2.15 Trust domain A collection of network nodes between which there is either direct or transitive trust in the authenticity of identifiers and the respecting of privacy requirements. 4 Acronyms CN Corporate telecommunication Network DNS Domain N

29、ame System IP Internet Protocol ISDN Integrated Services Digital Network NPI Numbering Plan Identification PISN Private Integrated Services Network SIP Session Initiation Protocol TON Type Of Number UCI Universal Communications Identifier URI Universal Resource Identifier WWW World-Wide Web 5 Backgr

30、ound Since the 1980s, the traditional way of providing voice services (including fax and modem services) in an enterprise has been through the use of a Private Integrated Services Network (PISN) employing circuit-switched technology. Users of a PISN are identified by numbers (telephone numbers). If

31、a user has been assigned a number, a second user can submit that number to the network in order to establish a call to the first user. Management of assigned numbers for a given network is conducted within a framework known as a numbering plan. This identification technique is similar to that employ

32、ed in (public) Integrated Services Digital Networks (ISDNs), where the numbering plan is ITU-T Recommendation E.164. Standard ECMA-155 describes numbering and addressing in a PISN. It describes the use of E.164 and private numbering plans in a PISN and defines a method of structuring private numberi

33、ng plans. It also specifies various forms of number that can be used for identifying parties. In the late 1990s, a trend of convergence between voice networks and data networks began, whereby the Internet Protocol (IP) started to be used to carry voice traffic (including associated signalling) along

34、side traditional data traffic. Identification in IP networks is based upon the Domain Name System (DNS), “Internet names“ (see section 6.2) and Universal Resource Identifiers (URIs), and this principle is therefore applicable also to voice traffic in IP networks. Because of the large investment by m

35、any enterprises in traditional telecommunication networks (PISNs), evolution towards the use of IP networks for voice is often planned to take place over a number of years. This means that PISNs and IP networks carrying voice traffic frequently need to co-exist within the same CN, and smooth interwo

36、rking between the two environments is necessary. This therefore means that the different methods of identification in the two types of network need to be understood and overcome. This Technical Report investigates this issue, with particular focus on the identification schemes supported by the QSIG

37、protocol in PISNs and SIP in IP networks. Work has been done in ETSI on naming (ETSI TR 101 326). The focus of that work was public telephony rather than CNs. - 3 - 6 Naming schemes 6.1 The meaning of a name The term “name“ is commonly applied to the identity of an entity in a telecommunication netw

38、ork, and the term “naming“ is applied to the technique of identifying entities by name. This is in contrast to the terms “address“ and “addressing“, which are commonly applied to the location at which an entity is to be found and the technique of identifying such locations. The general distinction b

39、etween a name and an address is that a name can remain with an entity even when that entity is mobile and moves between different addresses. 6.2 Names and users A name is often used to identify a human user, but it can also be used to identify other resources, e.g., a group of users or an automaton.

40、 For the purposes of this Technical Report a name is considered to be associated with a user. A user can have more than one name, either to reflect different roles of that user (e.g., business and private) or to reflect different networks in which the user has a presence. Even within a single networ

41、k a user can have more than one name for the same role, different names being used for different services. For example a name used for email might also be used for certain other services within the IP network, e.g., for voice or multimedia communications with other users in that or other IP networks

42、. However, an alternative name (in the form of a telephone number) is likely to be required for voice communication outside the IP environment, e.g., involving a public ISDN or PSTN. In order for a user to establish a communication session with a second user, the first user submits to his local netw

43、ork the name of the second user. It is the task of that network, in conjunction with other networks if necessary, to locate the user associated with that name and establish communication with that user. 6.3 Numeric and non-numeric names A name can comprise a string of digits (0 to 9), in which case

44、it is a numeric name, otherwise known as a number. Numbers are used in legacy circuit-switched networks, and therefore there are compatibility advantages in using numbers in IP networks. Also numbers are suitable for submission by a human user to a network by means of a device with a limited set of

45、keys, e.g., a conventional telephone. However, a non-numeric name can have a close correspondence with the everyday name of a user, and can therefore be easier to remember or guess. 6.4 Context of a name Ideally a name should be globally unique so that it has meaning anywhere in the world on a netwo

46、rk that supports that type of name. Such a name is said to be fully qualified. Sometimes, particularly on legacy systems, names are used that are meaningful only within a local context, e.g., within a given network or a given geographic region. A local name generally needs to be combined with additi

47、onal information to produce a fully qualified name. 6.5 Allocation of names Within a given context, names might be allocated to users on an arbitrary basis. However, this is not always the case. In some contexts names are allocated in accordance with some structure, e.g., organisational, geographic

48、or based on network topology. This makes routing easier but at the expense of lack of flexibility to accommodate long term or short term mobility. 6.6 Naming schemes in circuit-switched networks Naming schemes in circuit-switched networks (including PISNs, public ISDNs, PSTNs, cellular wireless netw

49、orks, etc.) are invariably based on numbers. Historically a number represented an address rather than a name, but with the advent of features such as number portability, terminal mobility and user mobility, there has been a gradual evolution over the last two decades towards a number representing a name rather than an address. This is completely true in cellular wireless - 4 - networks and is generally the case in modern PISNs. For the purposes of this Technical Report a number is assumed to be used as a name rather than an address. The numbering plan defined in ITU-T Recommend