1、 Standard ECMA-177 3rd Edition - December 2001 Standardizing Information and Communication Systems Private Integrated Services Network (PISN) - Specification, Functional Model and Information Flows - Call Transfer Supplementary Service Phone: +41 22 849.60.00 - Fax: +41 22 849.60.01 - URL: http:/www
2、.ecma.ch - Internet: helpdeskecma.ch . Standard ECMA-177 3rd Edition - December 2001 Standardizing Information and Communication Systems Private Integrated Services Network (PISN) - Specification, Functional Model and Information Flows - Call Transfer Supplementary Service (CTSD) Phone: +41 22 849.6
3、0.00 - Fax: +41 22 849.60.01 - URL: http:/www.ecma.ch - Internet: helpdeskecma.ch IW Ecma-177.doc 14-01-02 09,33 . Brief History This Standard is one of a series of ECMA Standards defining services and signalling protocols applicable to Private Integrated Services Networks (PISNs). The series uses I
4、SDN concepts as developed by ITU-T and conforms to the framework of International Standards for Open Systems Interconnection as defined by ISO/IEC. This particular Standard specifies the Call Transfer supplementary service. This Standard is based upon the practical experience of ECMA member companie
5、s and the results of their active and continuous participation in the work of ISO/IEC JTC1, ITU-T, ETSI and other international and national standardization bodies. It represents a pragmatic and widely based consensus. Compared to the 1st Edition of Standard ECMA-177 (published by ECMA in June 1992)
6、, the 2nd Edition (published by ECMA in September 1997) incorporated changes in order to achieve complete alignment with International Standard ISO/IEC 13865:1995(E) published by ISO/IEC in November 1995. Adopted as 3rd Edition of Standard ECMA-177 by the General Assembly of December 2001. - i - Tab
7、le of contents 1 Scope 1 2 Conformance 1 3 References (normative) 1 4 Definitions 2 4.1 External definitions 2 4.2 Other definitions 2 4.2.1 Additional network feature 2 4.2.2 Alerting 2 4.2.3 Answered 3 4.2.4 Call, basic call 3 4.2.5 Primary call 3 4.2.6 Secondary call 3 4.2.7 Transfer by Join 3 4.
8、2.8 Transfer by rerouteing 3 4.2.9 User A 3 4.2.10 User B 3 4.2.11 User C 3 5 Acronyms 3 6 SS-CT stage 1 specification 4 6.1 Description 4 6.1.1 General description 4 6.1.2 Qualifications on applicability to telecommunications services 4 6.2 Procedures 4 6.2.1 Provision/withdrawal 4 6.2.2 Normal pro
9、cedures 4 6.2.3 Exceptional procedures 5 6.3 Interactions with other supplementary services and ANFs 5 6.3.1 Calling Line Identification Presentation (SS-CLIP) 5 6.3.2 Connected Line Identification Presentation (SS-COLP) 5 6.3.3 Calling/Connected Line Identification Restriction (SS-CLIR) 6 6.3.4 Cal
10、ling Name Identification Presentation (SS-CNIP) 6 6.3.5 Connected Name Identification Presentation (SS-CONP) 6 6.3.6 Calling/connected Name Identification Restriction (SS-CNIR) 6 6.3.7 Completion of Calls to Busy Subscribers (SS-CCBS) 6 6.3.8 Completion of Calls on No Reply (SS-CCNR) 6 6.3.9 Call Fo
11、rwarding Services 6 6.3.10 Path Replacement (ANF-PR) 6 6.4 Interworking considerations 6 - ii - 6.4.1 User B and/or User C in another network 6 6.4.2 User A in another network 6 6.5 Overall SDL 7 7 SS-CT stage 2 specification for transfer by join 8 7.1 Functional model 8 7.1.1 Functional model descr
12、iption 8 7.1.2 Description of functional entities 8 7.1.3 Relationship of functional model to Basic Call functional model 9 7.2 Information flows 10 7.2.1 Definition of information flows 10 7.2.2 Relationship of information flows to basic call information flows 12 7.2.3 Examples of information flow
13、sequences 12 7.3 Functional Entity actions 15 7.3.1 Functional Entity actions of FE1 15 7.3.2 Functional Entity actions of FE2 15 7.3.3 Functional Entity actions of FE3 15 7.3.4 Functional Entity actions of FE4 15 7.4 Functional Entity behaviour 15 7.4.1 Behaviour of FE1 16 7.4.2 Behaviour of FE2 17
14、 7.4.3 Behaviour of FE3 19 7.4.4 Behaviour of FE4 20 7.5 Allocation of functional entities to physical locations 21 7.6 Interworking considerations 21 8 SS-CT stage 2 specification for transfer by rerouteing 22 8.1 Functional model 22 8.1.1 Functional model description 22 8.1.2 Description of functi
15、onal entities 23 8.1.3 Relationship of functional model to Basic Call functional model 23 8.2 Information flows 24 8.2.1 Definition of information flows 24 8.2.2 Relationship of information flows to basic call information flows 26 8.2.3 Examples of information flow sequences 26 8.3 Functional Entity
16、 actions 30 8.3.1 Functional Entity actions of FE1 30 8.3.2 Functional Entity actions of FE5 30 8.3.3 Functional Entity actions of FE6 30 8.3.4 Functional Entity actions of FE7 30 8.3.5 Functional Entity actions of FE4 30 8.4 Functional Entity behaviour 31 8.4.1 Behaviour of FE5 31 8.4.2 Behaviour o
17、f FE6 33 8.4.3 Behaviour of FE7 34 8.5 Allocation of functional entities to physical locations 35 - iii - Annex A - Bibliography 37 1 Scope This Standard specifies Supplementary Service Call Transfer (SS-CT), which is applicable to various basic services supported by Private Integrated Services Netw
18、orks (PISNs). Basic services are specified in ECMA-142. SS-CT is a supplementary service which enables a user to transform two of that users calls (of which one must be answered) into a new call between the other two users of the two calls. Supplementary service specifications are produced in three
19、stages, according to the method described in ETS 300 387. This Standard contains the stage 1 and stage 2 specifications of SS-CT. The stage 1 specification (clause 6) specifies the supplementary service as seen by users of PISNs. The stage 2 specification (clauses 7 and 8) identifies the functional
20、entities involved in the supplementary service and the information flows between them. This Standard contains two stage 2 specifications reflecting different ways of operating the service within the network: transfer by join and transfer by rerouteing. 2 Conformance In order to conform to this Stand
21、ard, a stage 3 standard shall specify signalling protocols and equipment behaviour that are capable of being used in a PISN which supports the supplementary services specified in this Standard. This means that, to claim conformance a stage 3 standard is required to be adequate for the support of tho
22、se aspects of clause 6 (stage 1) and clauses 7 and 8 (stage 2) which are relevant to the interface or equipment to which the stage 3 standard applies. 3 References (normative) The following standards contain provisions which, through reference in this text, constitute provisions of this Standard. Al
23、l standards are subject to revision, and parties to agreements based on this Standard are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. In the case of references to ECMA Standards that are aligned with ISO/IEC International Standards
24、, the number of the appropriate ISO/IEC International Standard is given in brackets after the ECMA reference. ECMA-133 Private Integrated Services Network (PISN) - Reference Configuration for PISN Exchanges (PINX) (International Standard ISO/IEC 11579-1) ECMA-142 Private Integrated Services Network
25、(PISN) - Circuit-mode 64 kbit/s Bearer Services - Service Description, Functional Capabilities and Information Flows (International Standard ISO/IEC 11574) ECMA-148 Private Integrated Services Network (PISN) - Specification, Functional Model and Information Flows - Identification Supplementary Servi
26、ces (International Standard ISO/IEC 14136) ECMA-163 Private Integrated Services Network (PISN) - Specification, Functional Model and Information Flows - Name Identification Supplementary Services (International Standard ISO/IEC 13864) ETS 300 387 Private Telecommunication Network (PTN); Method for t
27、he specification of basic and supplementary services (1994) ITU-T Rec. I.112 Vocabulary of terms for ISDNs (1993) ITU-T Rec. I.210 Principles of telecommunication services supported by an ISDN and the means to describe them (1993) ITU-T Rec. Z.100 Specification and description language (1999) - 2 -
28、4 Definitions For the purposes of this Standard, the following definitions apply. 4.1 External definitions This Standard uses the following terms defined in other documents: Basic Service (ITU-T Rec. I.210) Connection (ITU-T Rec. I.112) Private Integrated Services Network (PISN) (ECMA-133) Private I
29、ntegrated services Network eXchange (PINX) (ECMA-133) Service (ITU-T Rec. I.112) Signalling (ITU-T Rec. I.112) Supplementary Service (ITU-T Rec. I.210) User (ECMA-142) This Standard refers to the following basic call functional entities (FEs) defined in ECMA-142: Call Control (CC) Call Control Agent
30、 (CCA) This Standard refers to the following basic call inter-FE relationships defined in ECMA-142: r1 r2 r3 This Standard refers to the following basic call information flows defined in ECMA-142: Channel_Acknowledge request/indication Release request/indication Release response/confirmation Setup r
31、equest/indication Setup response/confirmation This Standard refers to the following basic call information flow elements defined in ECMA-142: Call History (CH) Connected Number (CN) Connected Subaddress (CS) This Standard refers to the following Connected Line Identification Presentation information
32、 flow elements defined in ECMA-148: Connected Number (CN) Connected Subaddress (CS) 4.2 Other definitions 4.2.1 Additional network feature A capability, over and above that of a basic service, provided by a PISN, but not directly to a PISN user. 4.2.2 Alerting The state of the secondary call when th
33、e called user is being alerted but has not yet answered. - 3 - 4.2.3 Answered The state of the primary or secondary call after the called user has answered. 4.2.4 Call, basic call An instance of the use of a basic service. 4.2.5 Primary call One of the calls involved in the transfer. In the case of
34、a transfer involving an unanswered call, the primary call is the answered call. In the case where both calls are already answered, the primary call is chosen arbitrarily by the network. 4.2.6 Secondary call The other call involved in the transfer. 4.2.7 Transfer by Join The effecting of transfer by
35、joining together the connections of the primary and secondary calls at User As PINX. 4.2.8 Transfer by rerouteing The effecting of transfer by establishing a new connection to replace all or part of the connections of the primary and secondary calls. 4.2.9 User A The served user, i.e. the user reque
36、sting Call Transfer. 4.2.10 User B The other user in User As primary call. 4.2.11 User C The other user in User As secondary call. 5 Acronyms AI Alerting Indication CC Call Control (functional entity) CCA Call Control Agent (functional entity) cfm confirmation CH Call History (information flow eleme
37、nt) CID Call Identity (information flow element) CN Connected Number (information flow element) CS Connected Subaddress (information flow element) CUG Closed User Group ED End Designation (information flow element) FE Functional Entity ind indication ISDN Integrated Services Digital Network LCI Loca
38、l Call Identities PINX Private Integrated services Network eXchange PISN Private Integrated Services Network req request - 4 - resp response RN Rerouteing Number (information flow element) SDL Specification and Description Language SS-CT Supplementary Service Call Transfer TDR Terminal Detail Reques
39、t TE Terminal Equipment TIDR Transfer Identity Result (information flow element) TINR Transfer Initiate Result (information flow element) TIVR Transfer Invoke Result (information flow element) 6 SS-CT stage 1 specification 6.1 Description 6.1.1 General description SS-CT is a supplementary service wh
40、ich enables a served user (User A) to transform two of that users calls into a new call between the other two users of the two calls (User B and User C). Each call can either be an incoming call to User A or an outgoing call from User A. After successful invocation of SS-CT, User B and User C will n
41、o longer be able to communicate with User A. One of the calls may be an outgoing call that has not been answered by the other user (User C). After successful invocation of SS-CT User A will no longer be able to communicate with User B. User B and User C will be in a position to communicate with each
42、 other as soon as User C has answered. NOTE The establishment of either call as part of a request for transfer is outside the scope of this Standard. This Standard assumes that both calls have already been established when the request for call transfer is made. This does not preclude an implementati
43、on whereby a single user request causes the establishment of a call and its subsequent transfer. 6.1.2 Qualifications on applicability to telecommunications services SS-CT is applicable to all basic services defined in ECMA-142. 6.2 Procedures 6.2.1 Provision/withdrawal SS-CT shall be generally avai
44、lable to all PISN users with the ability to invoke it. 6.2.2 Normal procedures 6.2.2.1 Activation/deactivation/registration/interrogation Not applicable. 6.2.2.2 Invocation and operation A Call Transfer request from a user (User A) shall be accepted only if it identifies two of that users calls wher
45、e: - both calls (to/from User B and to/from User C) have been answered; or - one call (to/from User B) has been answered and the other is an outgoing call which is alerting User C; or - one call (to/from User B) has been answered and the other is an unanswered outgoing call to User C in a non-ISDN.
46、It shall not be necessary for User A to place either call on hold prior to invocation, although either or both calls may be held. - 5 - The network shall ensure that the transfer attempt does not allow an illegal connection to be made, for example one which would infringe CUG restrictions between Us
47、er B and User C, or one which would result in a connection with a mixture of incompatible bearer capabilities. NOTE 1 It is User As responsibility to ensure that the two calls are otherwise compatible. Bearer capabilities shall be considered compatible if they are the same. Bearer capabilities shall
48、 also be considered compatible if the only attribute that differs is Information Transfer Capability and if one call has the value “Speech“ and the other call is interworking with a non-ISDN and has the value “ 3,1 kHz audio.“ NOTE 2 The provision of interworking functions between different bearer c
49、apabilities is outside the scope of this Standard. The result of successful Call Transfer shall be a new call between users B and C, at which point the original connections to User A shall be released. Both users B and C shall be informed of the transfer and the name and number of the other user (if available and not subject to restriction), and whether the other user is still being alerted. The network shall permit subaddresses to be exchanged between User B and User C after transfer. If User C is being alerted at the time of completio
