CEPT T S 22-02 E-1987 Supplementary Service Call Waiting《补充业务呼叫等待》.pdf

1、- CEPT T/S*22:02*E 87 2326434 0007820 b i its22-02 Page E 1 Recommendation T/S 22-02 (by correspondence, May 1987) SUPPLEMENTARY SERVICE “CALL WAITING” Recommendation proposed by Working Group T/WG 11 “Signalling, Protocols and Switching” (SPS) Text of the Recommendation adopted by the “Telecoinmitl

2、iicatioons” Commission : “The European Conference of Postal and Telecommunications Administrations, considering - the common CEPT approach to the ISDN and general CEPT assumptions and policies for the evolution towards - the I. Series Recommendations of the CCITT, as well as other CCITT Recommendati

3、ons on ISDN, to which - the need for CEPT Administrations to have more precise answer to their specific European requirements, i.e. to - the need for CEPT Administrations to have as a base a comprehensive set of Recommendations, in order to ISDN, CEPT Administrations have contributed most significan

4、tly, select and further dene material from CCITT Recommendations, promote and strengthen European harmonisation, O recommends to the members of the CEPT that the information flows, selection and location of network functions to support the supplementary service “Call Waiting” be in accordance with t

5、he guidelines and specifications given in the attached text. ” Edition of August 15, 1987 .-, CEPT T/S*22-02*E 7 m 232b4L4 000723 m TIS 22-02 E Page 2 1. 2. 3. 4. 4.1. 4.2. 4.3. DEFINITION Call waiting enables a basic access user to be notified of an incoming call when both B-channels are in use. Th

6、e user then has the choice of accepting, rejecting or ignoring the waiting call. Note. Application of call waiting indication in the case when there is only one B channel busy is for further study. PROSE DESCRIPTION The prose description considered is that provided in Recommendation T/SF 3 1-07. DYN

7、AMIC DESCRIPTION The dynamic description is contained in Appendix 1. It consists of SDL diagram showing the process of the network as a whole. FUNCTIONS AND INFORMATION FLOWS Assumed network architecture The assumed network architecture for ?call waiting? is shown in Figure 1 (T/S 22-02). (i) Servic

8、e requesting terminal. (2) Network access providing exchange. (4) Remote exchange. (7) Remote terminal. Figure 1 (T/S 22-02). Network architecture for ?call waiting? supplementary service. Identification of functions The identification and allocation of Basic and Additional Elementary Functions (BEF

9、?s and AEF?s) is provided in Appendix 2. It consists of the matrices which map the above-mentioned Elementary Functions between network components according to the assumed network architecture. These matrices are the normal method used by ENF for functional description and allocation. Information fl

10、ows The Appendix 3 gives the information flow diagram indicating the interaction of the identified functions based on the overall service description and the SDL diagram. The only functions inserted in the informa- tion flow diagram are those required for ?call waiting? supplementary service. 1 . Ed

11、ition of August 15, 1987 TIS 22-02 E Appendix 1, Page 1 BOTH B CHANNELS IN USE CALL DEMAND NORMAL CALL PREPARATION r -LNOTE 2 NETWORK DEFINED I 1 OFFER CALL NOTE 74- NOTE START TP WAITING FOR RESPONSE CHANNELS EQUEST FROM C TO CLEAR CALL DISCONNECT (CAUSE: NO COMPATIBLE I TERMINALS) CALL c-B I I Edi

12、tion of August 15, 1987 Y, f STOP TP STOP TP r DISCONNET NOTIFY C INFORMED USER BBEING -L g CALL C-B Y r START TI -jNOTE 10 L CALL C-6 WAITING OVERALL SDL DIAGRAM OF CALL WAITING _ F_-_ A U c W v) U am o. !Yb ! I- +o+ Y a I 4 II) A I CEPT T/S*22-02*E 87 232b4L4 0007823 L TIS 22-02 E Appendix 1, Page

13、 2 . - _ 7 b r w Y L L CI 9, 2 2% U U h Y t O 8 x d !2 m r Y L r- - Edition of August 15, 1987 I TIS 22-02 E Appendix 1, Page 3 Notes to overall SDL-diagram of “call waiting” 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. The overall SDL-diagram represents the network as a whole. Normal call preparation

14、 comprises the normal call Set-up, the call set-up on the access of B, and provisions of network resources for call C-B. The activation of call waiting and the notification about the incoming waiting call may be distinctive with respect to the origin belonging or not the same closed user group/busin

15、ess group/ISPBX, etc. as B. The maximum number of waiting calls allowed is a national option. Whether and if so, to which degree, activation/deactivation is supported by the network may be network dependent. The call may be offered depending on the maximum number of calls allowed on the basic access

16、. Completion of the call C-B will proceed as for a basic call. Tp corresponds to the use of T 303 of layer 3 D-channel protocol. As a national option, user C may receive a special indication with regard to the call waiting. TI: limits the duration of the call in the waiting condition. The duration o

17、f TI is for further study. Request from B to hold active call can be performed separately from the request to connect to the waiting call. It should be noted that timer TI should not be stopped until the receipt of the request to connect to the waiting call. The same conditions with respect to a new

18、 incoming call for B apply as from the state “both B channels in use”. From this state (one call active, one Cali held), the same user possibilities apply as from the corresponding state of the “three party service”, and this matter requires further study. Edition of August 15, 1987 TIS 22-02 E Appe

19、ndix 2, Page 1 MATRIX FOR ALLOCATION OF BASIC ELEMENTARY FUNCTIONS (BEF) TO NETWORK COMPONENTS SUPPLEMENTARY SERVICE: CALL WAITING BEF BEF100 Characteristics of service requested examination BEFIOl Connection elements type determination BEFlO2 User-network access resources reservation (channels) BEF

20、103 Transit resources reservation BEF104 Communication references handling BEFIOS Establishment control BEFIO Release control BEF107 Service related authorisations examination BEF108 User-network signalling handling (layer 3) BEF109 Inter-exchange signalling handling (user Dart) BEFI10 Supplementary

21、 services compatibility checking BEFlll Building up of and maintaining dynamic information related to the call/connection BEFl12 Signalling intenvorking BEFI 13 Priority BEFI 14 Queue handling Service requesting terminal Network access Data providing base exchange (2) (3) Remote exchange (4) (Option

22、ally implemented) (Optionally implemented) (Optionally implemented) Network interworkinl unit (5) Specialised service centre (6) Remote terminal Edition of August 15, 1987 CEPT T/S*22-02*E 87 m 2326434 000782b 7 m TIS 22-02 E Appendix 2, Page 2 MATRIX FOR ALLOCATION OF BASIC ELEMENTARY FUNCTIONS (BE

23、F) TO NETWORK COMPONENTS SUPPLEMENTARY SERVICE: CALL WAITING BEF BEF200 ISDN number identification BEF20 1 Called number analysis (address analysis) BEF202 Routing information examination (if provided) BEF203 Predetermined specific routing BEF204 Connection path selection BEF205 Rerouting BEF300 Hol

24、d and release of user- network access resources (channels) BEF301 Hold and release of transit ressources (circuits) BEF302 Insertion and suppression of specific equipment BEF303 Tones, announcements and display information BEF304 User-network signalling handling (layers 1-2) BEF305 Inter-exchange si

25、gnalling handling (message transfer) BEF306 Path search inside switching unit BEF307 Synchronisation handling BEF308 Timing handling BEF309 Line service marking BEF310 Real time clock Edition of August 15, 1987 CEPT T/S*22-02*E 87 2326434 0007827 9 W TIS 22-02 E Appendix 2, Page 3 MATRIX FOR ALLOCAT

26、ION OF ADDITIONAL ELEMENTARY FUNCTIONS (AEFs) TO NETWORK COMPONENTS SUPPLEMENTARY SERVICE: CALL WAITING I Network access providing exchange (2) X Remote exchange Network interworkin8 unit Service requesting terminal (1) Data base (3) AEF AEFOO Insertion and suppression of additional resources (tones

27、, etc.) X AEFOI Line hunting i AEFOL Direct dialling in AEF03 AEF04 Subscribers dedicated storage X AEFO5 Bridge AEF06 User-network access resources hold AEF07 Hold of communication X X AEFOS X Additional subscriber signalling AEF09 Additional inter-exchange signalling AEFIO Multi-call handling X AE

28、FI 1 Internal call initialisation I AEFI2 Access/route restriction I AEF13 Subscriber call data registration AEF14 Edition of August 15, 1987 F=V, TIS 22-02 E Appendix 2, Page 4 List of identified basic and additional elementary functions (EFs) for the ISDN BASIC EFs RELATED TO CONNECTION TYPES BEF1

29、00 BEF101 BEF102 BEF103 BEF104 BEFlO5 BEF106 BEF107 BEF108 BEF 109 BEFllO BEFlll BEF112 BEF113 BEF114 BEF200 BEF201 BEF202 BEF203 BEF204 BEF205 BEF300 BEF301 BEF302 BEF303 BEF304 BEF305 BEF306 BEF307 BEF308 BEF309 BEF3 10 BEF400 BEF40 1 BEF402 BEF403 BEF404 BEFSOO BEF501 BEF6OO BEF601 BEF602 BEF603

30、BEF604 BEF605 CONNECTION HANDLING characteristics of service requested examination connection elements type determination user-network access resources reservation (channels) transit resources reservation communication references handling establishment control release control service related authori

31、sations examination user-network signalling handling (layer 3) inter-exchange signalling handling (user part) supplementary services compatibility checking building up of and maintaining dynamic information relating to the call/connection signalling interworking priority queue handling ROUTING ISDN

32、number identification called number analysis (address analysis) routing information examination (if provided) predetermined specific routing connection path selection rerouting RESOURCES HANDLING hold and release of user-network access resources (channels) hold and release of transit resources (circ

33、uits) insertion and suppression of specific equipment tones, announcements and display information user-network signalling handling (layers 1-2) inter-exchange signalling handling (message transfer) path search inside switching tinit synchronisation handling timing handling line service marking real

34、 time clock SUPERVISION user-network access resources monitoring transit resources monitoring continuity checking detection of congestion semi-permanent connection scanning OPERATION AND MAINTENANCE management of subscriber data fault report CHARGING charging management charging registering charging

35、 recording billing accounting charging information Edition of August 15, 1987 BEF700 BEF70 1 BEF702 BEF703 BEF704 BEF705 BEF706 BEF707 CEPT T/S*22-02*E 7 2326434 0007829 2 -_- - TIS 22-02 E Appendix 2, Page 5 INTERWORKING rate adaption protocol conversion calling number analysis numbering interworki

36、ng special routing algorithms negotiation notification charging for interworking ADDITIONAL EFs RELATING TO SUPPLEMENTARY SERVICES AEFOO AEFO1 AEFO2 AEF03 AEF04 AEFO 5 AEFO6 AEF07 AEF08 AEF09 AEF 1 O AEF11 AEF12 AEF13 AEF 14 insertion and suppression of additional resources (tones, etc.) line huntin

37、g” direct dialling in” number determination subscribers dedicated storage bridge user-network access resources hold hold of communication additional subscriber signalling additional inter-exchange signalling multi-call handling internal call initialisation access/route restriction subscriber call da

38、ta registration data display option Short description of Elementary Features BASIC EFs RELATED TO CONNECTION TYPES 1 CONNECTION HANDLING BEF100 characteristics of service requested exarnination Feature of an ISDN component to determine the required service characteristics (certain attributes of the

39、bearer service and optional supplementary services) of a call by means of examination of information sent by calling terminal. BEF101 connection elements type determination Feature of an ISDN component to determine connection types and connection elements necessary to provide the requested service.

40、BEF102 user-network access resources reservation (channels) Feature of an ISDN component to determine the type of user-network access (basic, primary), the state of the resources (channels availability) and to reserve the channel(s) needed for establishing the access connection element. BEF103 trans

41、it resources reservation Feature of an ISDN component to reserve the transit connection element, based on the state of the resources. BEF104 commirnication references handling Feature of an ISDN component to assign a local reference (at the access interface) to the call and an internal reference (at

42、 internal interface) to the connection, and to clear these references when the call/connection is cleared/released. BEFlOS establishment control Feature of an ISDN component to set up a connection through the component. BEF106 release control Feature of an ISDN component to release a connection thro

43、ugh the component. BEF 107 service related authorisations examination Feature of an ISDN component to determine the authorisations (calling or called user) relating to basic and supplementary services that have been subscribed to. O * Inclusion is for further study. Edition of August 15, 1987 -7 7 C

44、EPT T/S*22-02*E 87 W 232bYL4 0007830 9 H TIS 22-02 E Appendix 2, Page 6 BEF108 user-to-network signalling handling (layer 3) Feature of an ISDN component to support the layer 3 protocol of the user-network signalling system. Note. For layers 1 and 2, see paragraph 3 “Resources handling”. BEF109 inte

45、r-exchange signalling handling (user part) Feature of an ISDN component to support the user part of the inter-exchange signalling system. BEF110 supplementary services compatibility checking Feature of the network to check the compatibility of requested supplementary services, e.g. : - with requeste

46、d bearer service or teleservice; - with other requested supplementary services, and to verify coherence between parameters that may be associated. BEF111 building-up of and maintaining of dynamic information related to the call/connection Feature of an ISDN component to compile information related t

47、o the call/connection, e.g. : - resources needed (connection type, connection elements, channels, circuits); - details of call in progress; - supplementary services effected and associated parameters. BEF112 signalling interworking Feature of an ISDN component to support interworking functions betwe

48、en signalling systems; BEF113 priority Feature of an ISDN component to handle specific calls with priority (e.g. in the case of overload or degraded mode of operation). Note. Needs reexamination under consideration of EFs associated with GF, “operation and maintenance”. BEF114 queue handling Feature

49、 of an ISDN component to store requests in a queue, in order to handle this information later in a predefined order. 2 ROUTING BEF200 ISDN number identijcation Feature of an ISDN component to identify the ISDN number of the user-network interface. This information is limited to that included within the ISDN numbering plan. BEF201 called number analysis (address analysis) Feature of an ISDN component to analyse called ISDN number sent by the calling terminal in the call set-up phase. BEF202 routing information examination (ifprovid