1、INTERNATIONAL TELECOMMUNICATION UNION ITU-T TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU SPECIFICATIONS OF SIGNALLING SYSTEM No. 7 Q.733 (03/93) STAGE 3 DESCRIPTION FOR CALL COMPLETION SUPPLEMENTARY SERVICES USING SS No. 7 CLAUSE 2 - CALLHOLD (HOLD) CLAUSE 4 - TERMINAL PORTABILITY (TP) ITU-T Reco
2、mmendation Q.733 (Previously “CCITT Recommendation”) COPYRIGHT International Telecommunications Union/ITU TelecommunicationsLicensed by Information Handling ServicesITU-T RECMN*Q.733 93 m 48b259L 0585202 984 m FOREWORD The Telecommunication Standardization Sector (ITU-T) is a permanent organ of the
3、International Telecom- munication Union. The -T is responsible for studying technical, operating and tariff questions and issuing Recommendations on them with a view to standardizing telecommunications on a worldwide basis. The World Telecommunication Standardization Conference (WTSC). which meets e
4、very four years, established the topics for study by the -T Study Groups which, in their turn, produce Recommendations on these topics. -T Recommendation 4.733, clauses 2 and 4 was prepared by the ITU-T Study Group XI (1988-1993) and was approved by the WSC (Helsinki, March 1-12. 1993). NOTES 1 As a
5、 consequence of a reform process within the International Telecommunication Union (ITU), the CCITT ceased to exist as of 28 February 1993. In its place, the Telecommunication Standardization Sector (ITU-T) was created as of 1 March 1993. Similarly, in this reform process, the CCIR and the IFRB have
6、been replaced by the Radiocommunication Sector. In order not to delay publication of this Recommendation, no change has been made in the text to references containing the acronyms “CCITT, CCIR or IFRB” or their associated entities such as Plenary Assembly, Secretariat, etc. Future editions of this R
7、ecommendation will contain the proper terminology related to the new ITU structure. 2 telecommunication administration and a recognized operating agency. In this Recommendation, the expression “Administration” is used for conciseness to indicate both a O ITU 1994 All rights reserved. No part of this
8、 publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from the ITU. COPYRIGHT International Telecommunications Union/ITU TelecommunicationsLicensed by Information Handling ServicesITU-T RE
9、CMN*Q-733 93 4862593 0585203 830 CONTENTS 2 Call Hold (HOLD) . 2.1 Definition 2.2 Description 2.3 Operational requirements 2.4 Coding requirements . 2.5 Signalling requirements Interactions with other supplementary services 2.6 2.7 Interaction with other networks 2.8 Signalling flows 2.9 Parameter v
10、alues (timers) . 2.10 Dynamic description . 4 Terminal Portability (TP) . 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 4.10 Definition Description Operational requirements Coding requirements . Signalling requirements Interactions with other supplementary services Signalling flows Dynamic description . Inter
11、actions with other networks . Parameter values (timers) . Recommendation 4.733 (03/93) Page 1 1 1 2 2 2 4 5 6 6 6 7 7 7 8 8 8 10 12 12 12 12 1 COPYRIGHT International Telecommunications Union/ITU TelecommunicationsLicensed by Information Handling ServicesITU-T RECMN+Q.733 93 48b259L 0585204 757 Reco
12、mmendation 4.733 STAGE 3 DESCRIPTION FOR CALL COMPLETION SUPPLEMENTARY SERVICES USING SS No. 7 (Helsinki, 1993) 2 Call Hold (HOLD) 2.1 Definition The Call Hold (HOLD) supplementary service, allows a user to interrupt communications on an existing call and then subsequently, if desired, re-establish
13、communications. 2.2 Description This clause is specific to Signalling System No.7 protocol for the ISDN User Part. Stage 3 identifies the protocol procedures and switching functions needed to support a telecommunications service. 2.2.1 General description A call may be placed on hold by the calling
14、user, at any time after the call has been answered or additionally as a service provider option: 1) 2) after alerting has commenced, or after the calling user has provided all of the information necessary for processing the call. A call may be placed on hold by the called user, at any time after the
15、 call has been answered and before call clearing has begun. The Call Hold service includes the Retrieve operation which re-establishes communication on a B-channel between the served user and the held party. The stage 1 definitions for the HOLD supplementary service are given in Recommendation 1.253
16、.2. The stage 2 descriptions are given in Recommendation 4.83.2. The stage 3 DSS 1 description is given in Recommendation 4.953.2. This stage 3 description of Call Hold supplementary service uses the ISDN User Part protocol as defined in Recommendations 4.761 -4.764. 2.2.2 Specific terminology For t
17、he purposes of this Recommendation, the following definitions apply: User A: User A is a terminal equipment which invokes the HOLD supplementary service for a given call. User A is the served user. User B: User B is a terminal equipment engaged in the given call to user A which invokes the HOLD supp
18、lementary service. User B is the non-served user. 2.2.3 See 2.3lI.253.2. Qualification on the applicability to telecommunication services 2.2.4 State definitions No specific state definitions are required. Recommendation Q.733 (03/93) 1 COPYRIGHT International Telecommunications Union/ITU Telecommun
19、icationsLicensed by Information Handling ServicesITU-T RECMN*Q.733 93 H LI862593 0585205 b93 H 2.3 Operational requirements 23.1 Provision/withdrawai See 2.3.1fi.253.2. 2.3.2 Not applicable. Requirements on the originating network side 2.3.3 Requirements in the network No specific requirements are n
20、eeded in the network. 23.4 Not applicable. Requirements on the terminating network side 2.4 Coding requirements For the HOLD supplementary service, the Call Progress message containing the Generic notification indicator parameter, shall be used to send the appropriate notification towards the remote
21、 party. The Event indicator is set to “Progress”. The following notification descriptions are used: - Remote-hold - Remote-retrieval The Generic notification indicator parameter field shall be coded as shown in Table 2-1. TABLE 2-1/Q.733 Coding of the Generic notification indicator parameter Bits De
22、scription 11 11001 Remote hold 1111010 Remote retrieval The Generic notification indicator parameter is accompanied by the parameter compatibility information parameter. The procedures for the compatibility are defined in 2.9.5/Q.764. 2.5 Signalling requirements 2.5.1 ActivatioIdeactivatiodregistrat
23、ion Not applicable. 2.5.2 Invocation and operation 2.5.2.1 The originating local exchange is the exchange where the service is controlled. The originating local exchange for this description is not necessarily the originating exchange for the basic call. Actions at the originating local exchange 2 R
24、ecommendation Q.733 (03/93) COPYRIGHT International Telecommunications Union/ITU TelecommunicationsLicensed by Information Handling ServicesITU-T RECMN*Q-733 93 D 48b259L 058520b 52T 2.5.2.1.1 Nod operation 2.5.2.1.1.1 Hold request When a call is placed on hold, or when a hold notification is receiv
25、ed from the access signalling system, a notification is conveyed in a CPG message towards the remote user, indicating that the call has been placed on hold. The CE message shall only be sent after the ACM has been received. 2.5.2.1.1.2 Retrieve request When a call that was placed on hold is retrieve
26、d, or when a retrieve notification is received from the access signalling system, a notification is conveyed in a CPG message towards the remote user, indicating that the call has been retrieved. 2.5.2.1.2 Exceptional procedures No exceptional procedures are identified. 2.5.2.2 Actions at the transi
27、t exchange 2.5.2.2.1 Normal operation A transit exchange shall transfer the notification indication to the succeeding exchange. 2.5.2.2.2 Exceptional procedures No exceptional procedures are identified. 2.5.2.3 Actions at the outgoing intemational gateway exchange 2.5.2.3.1 Normal operation An outgo
28、ing international gateway exchange shall transfer the notification indication to the succeeding exchange. 2.5.2.3.2 Exceptional procedures No exceptional procedures are identified. 2.5.2.4 Actions at the incoming international gateway exchange 2.5.2.4.1 Normal operation An incoming international gat
29、eway exchange shall transfer the notification indication to the succeeding exchange. 2.5.2.4.2 Exceptional procedures No exceptional procedures are identified. 2.5.2.5 The destination local exchange for this description is not necessarily the destination exchange for the basic call. Actions at the d
30、estination local exchange 2.5.2.5.1 Normal operation At the exchange where user B is connected, the notification indication contained in the CPG message is passed on to the access signalling system of user B. 2.5.2.5.2 Exceptional procedures No exceptional procedures are identified. Recommendation Q
31、.733 (03/93) 3 COPYRIGHT International Telecommunications Union/ITU TelecommunicationsLicensed by Information Handling ServicesITU-T RECMN*Q-733 73 4862591 0585207 466 2.6 2.6.1 Call waiting (CW) No impact on ISUP. Interactions with other supplementary services 2.6.2 Call transfer services No applic
32、able interaction at this time. 2.6.3 No impact on ISUP. Connected line identification presentation (COLP) 2.6.4 No impact on ISUP. Connected line identification restriction (COLR) 2.6.5 No impact on ISUP. Calling line identifcation presentation (CLIP) 2.6.6 No impact on ISUP. Calling line idenHicati
33、on restriction (CLIR) 2.6.7 Cl& user group (CUG) No impact on ISUP. 2.6.8 Conference calling (CONF) No impact on ISUP. 2.6.9 Direct dialling in DI) No impact on ISUP. 2.6.10 Call diversion services (CDIV) No impact on ISUP. 2.6.10.1 Call forwarding busy (CFB) No impact on ISUP. 2.6.10.2 Call forward
34、ing no reply (CFNR) No impact on ISUP. 2.6.10.3 Call forwarding unconditional (CFU) No impact on ISUP. 2.6.10.4 Call deflection (CD) No impact on ISUP. 2.6.11 Line hunting (LH) No impact on ISUP. 2.6.12 Three Party service (3PTY) No impact on ISUP. 4 Recommendation Q.733 (03/93) COPYRIGHT Internatio
35、nal Telecommunications Union/ITU TelecommunicationsLicensed by Information Handling ServicesITU-T RECMN*Q.733 93 = 48b259L 0585208 3T2 2.6.13 User-to-user signalling (UUS) No impact on ISUP. 2.6.13.1 User-to-user signalling service 1 (UUS 1) No impact on ISUP. 2.6.13.2 User-to-user signalling servic
36、e 2 (UUS 2) No impact on ISUP. 2.6.13.3 User-to-user signalling service 3 (UUS 3) No impact on ISUP. 2.6.14 Multiple subscriber number (MSN) No impact on ISUP. 2.6.15 Call hold (HOLD) Not applicable. 2.6.16 Advice of charge (AOC) No impact on ISUP. 2.6.17 Sub-addressing (SUB) No impact on ISUP. 2.6.
37、18 Terminai portability (“i) No impact on ISUP. 2.6.19 No applicable interaction at this time. 2.6.20 Malicious call identification (MCID) No impact on ISUP. 2.6.21 Reverse charging (REV) No applicable interaction at this time. Completion of calls to busy subscriber (CCBS) 2.6.22 No impact on ISUP.
38、Multi-level precedence and preemption (MLPP) 2.6.23 Private numbering plan (PNP) No applicable interaction at this time. 2.6.24 International telecommunication charge card No applicable interaction at this time. 2.7 Interaction with other networks In the case of interaction with PSTN, it is a networ
39、k provider option to supply the remote user with an in-band indication. In the case of interactions with networks which do not provide the notification procedure, the interworking exchange will discard the CPG message containing the notification indication. The call will then be completed according
40、to the basic call procedure as described in Q.764. Recommendation Q.733 (03/93) 5 COPYRIGHT International Telecommunications Union/ITU TelecommunicationsLicensed by Information Handling ServicesITU-T RECMN*Q.733 93 LI862593 0585209 239 2.8 Signalling flows Examples of information flow for the CALL H
41、OLD supplementary service are shown in Figure 2-1 and Figure 2-2. 2.9 Parameter values (timers) No specific timers are required. NOTE - In the case of Hold during waiting for answer, if Tg (the . .waiting Answer Timer, see Annex NQ.764) expires, the cai1 will be released according to the basic call
42、procedure. 2.10 Dynamic description No dynamic descriptions (SDLs) are required. Originating Trans% Destination User A local axchange ezhmge bcd ezhmge User 6 I I L n SET-UP ALERTING c HOD -. , Hou) ACK ( RETRIEVE RETRIEVE ACK c ACM CPG (retrieve) ACM , CPG CPG (rdrieve) I J L SET-UP ALERTING NOTIN
43、, (rariwe) I J T1135P091181 IAM Inltlal address message ACM Address complete message CPG Call progress message FIGURE 2-1/Q.733 Hold and retrieve during waiting for answer 6 Recommendation Q.733 (03/93) COPYRIGHT International Telecommunications Union/ITU TelecommunicationsLicensed by Information Ha
44、ndling ServicesL ITU-T RECMN*t-733 93 m 4862593 0585210 T50 m Otignaing TWlSit Destin& User A local exdiange exchange local excharige user B l I 1 HOLD ACK RETRIEVE ACTIVE CALL (A c - B) HOU) RETRIEVEACK CPG (held) CPG ( reirim) CPG (held) , Tt 13590Cb91/a)2 FIGURE 2-214.733 Hdd and retrieve during
45、active phase 4 Terminal Portabiiity (TP) 4.1 Definition The Terminal Portabiiity supplementary service allows a user to move a terminal from one socket to another within one given basic access during the active state of the call. It also allows a user to move a call from one terminal to another term
46、inal within one given basic access during the active phase of the call. 4.2 Description 4.2.1 General description By requesting a SuspendResume procedure the calling as well as the called user is enabled to move the terminal by means of unplugging and reconnecting it. In addition to that it is possi
47、ble to replace the terminal by another compatible one or to suspend and resume a call without changing the terminal or the socket. Recommendation Q.733 (03/93) 7 COPYRIGHT International Telecommunications Union/ITU TelecommunicationsLicensed by Information Handling ServicesITU-T RECMN*Q-733 93 48b25
48、91 0585211 997 The stage 1 definition for the Terminal Portability supplementary service is given in Recommendation 1.253.4. The stage 2 description is given in Recommendation 4.85.4. The stage 3 DSS 1 description is given in Recommenda- tion 4.953.4. This stage 3 description of terminal portability
49、 supplementary service uses the ISDN User Part protocol as defined in Recommendations 4.761-4.764 and 4.766. 4.2.2 Specifc terminology Served user: The user sending Suspend and Resume. Suspend: Message sent to suspend a call. Resume: Message sent to resume a call. 4.2.3 See Recommendation 1.253.4. Qualification on the applicability to telecommunication services 4.2.4 State definitions No specific state definitions are required. 4.3 Operational requirements 4.3.1 Provisionhvithdrawal See Recommendation 1.253.4. 43.2 Not applicable. Requirements on the o
