1、INTERNATIONAL TELECOMMUNICATION UNION)45G134 1 TELECOMMUNICATION (03/93)STANDARDIZATION SECTOROF ITU30%#)&)#!4)/.3G0G0/&G0G03).!,).3934%-G0G0.O G0G0 34!%G0G0 G0G0$%3#2)04)/.G0G0&/2G0G0#!,#/-0,%4)/.G0G03500,%-%.4!293%26)#%3G0G053).G0G033G0G0.O G0G0 #,!53%G0G0 G0G0 G0G0#!,G0(/,$G0G0 (/,$G9#,!53%G0G0 G
2、0G0 G0G04%2-).!,G0G00/24!“),)49G0G0 40G9)45G134G0G02ECOMMENDATIONG0G01 (Previously “CCITT Recommendation”)FOREWORDThe ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of the International Telecom-munication Union. The ITU-T is responsible for studying technical, operating an
3、d tariff questions and issuingRecommendations on them with a view to standardizing telecommunications on a worldwide basis.The World Telecommunication Standardization Conference (WTSC), which meets every four years, established thetopics for study by the ITU-T Study Groups which, in their turn, prod
4、uce Recommendations on these topics.ITU-T Recommendation Q.733, clauses 2 and 4 was prepared by the ITU-T Study Group XI (1988-1993) and wasapproved by the WTSC (Helsinki, March 1-12, 1993)._NOTES1 As a consequence of a reform process within the International Telecommunication Union (ITU), the CCITT
5、ceased to exist as of 28 February 1993. In its place, the ITU Telecommunication Standardization Sector (ITU-T) wascreated as of 1 March 1993. Similarly, in this reform process, the CCIR and the IFRB have been replaced by theRadiocommunication Sector.In order not to delay publication of this Recommen
6、dation, no change has been made in the text to references containingthe acronyms “CCITT, CCIR or IFRB” or their associated entities such as Plenary Assembly, Secretariat, etc. Futureeditions of this Recommendation will contain the proper terminology related to the new ITU structure.2 In this Recomme
7、ndation, the expression “Administration” is used for conciseness to indicate both atelecommunication administration and a recognized operating agency. ITU 1994All rights reserved. No part of this publication may be reproduced or utilized in any form or by any means, electronic ormechanical, includin
8、g photocopying and microfilm, without permission in writing from the ITU.Recommendation Q.733 (03/93) iCONTENTSRecommendation Q.733 (03/93)Page2 Call Hold (HOLD) . 12.1 Definition 12.2 Description 12.3 Operational requirements 22.4 Coding requirements. 22.5 Signalling requirements 22.6 Interactions
9、with other supplementary services 42.7 Interaction with other networks 52.8 Signalling flows 62.9 Parameter values (timers) . 62.10 Dynamic description. 64 Terminal Portability (TP). 74.1 Definition 74.2 Description 74.3 Operational requirements 84.4 Coding requirements. 84.5 Signalling requirements
10、 84.6 Interactions with other supplementary services 104.7 Interactions with other networks. 124.8 Signalling flows 124.9 Parameter values (timers) . 124.10 Dynamic description. 12Recommendation Q.733 (03/93) 1Recommendation Q.733Recommendation Q.733 (03/93)STAGE 3 DESCRIPTION FOR CALL COMPLETION SU
11、PPLEMENTARYSERVICES USING SS NO. 7(Helsinki, 1993)2 Call Hold (HOLD)2.1 DefinitionThe Call Hold (HOLD) supplementary service, allows a user to interrupt communications on an existing call and thensubsequently, if desired, re-establish communications.2.2 DescriptionThis clause is specific to Signalli
12、ng System No.7 protocol for the ISDN User Part. Stage 3 identifies the protocolprocedures and switching functions needed to support a telecommunications service.2.2.1 General descriptionA call may be placed on hold by the calling user, at any time after the call has been answered or additionally as
13、a serviceprovider option:1) after alerting has commenced, or2) 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 call has been answered and before call clearing hasbegun.The Call Hold se
14、rvice includes the Retrieve operation which re-establishes communication on a B-channel between theserved user and the held party.The stage 1 definitions for the HOLD supplementary service are given in Recommendation I.253.2. The stage 2descriptions are given in Recommendation Q.83.2.The stage 3 DSS
15、 1 description is given in Recommendation Q.953.2.This stage 3 description of Call Hold supplementary service uses the ISDN User Part protocol as defined inRecommendations Q.761-Q.764.2.2.2 Specific terminologyFor the purposes of this Recommendation, the following definitions apply:User A: User A is
16、 a terminal equipment which invokes the HOLD supplementary service for a given call. User A is theserved user.User B: User B is a terminal equipment engaged in the given call to user A which invokes the HOLD supplementaryservice. User B is the non-served user.2.2.3 Qualification on the applicability
17、 to telecommunication servicesSee 2.3/I.253.2.2.2.4 State definitionsNo specific state definitions are required.2 Recommendation Q.733 (03/93)2.3 Operational requirements2.3.1 Provision/withdrawalSee 2.3.1/I.253.2.2.3.2 Requirements on the originating network sideNot applicable.2.3.3 Requirements in
18、 the networkNo specific requirements are needed in the network.2.3.4 Requirements on the terminating network sideNot applicable.2.4 Coding requirementsFor the HOLD supplementary service, the Call Progress message containing the Generic notification indicatorparameter, shall be used to send the appro
19、priate notification towards the remote party.The Event indicator is set to “Progress”.The following notification descriptions are used: Remote-hold Remote-retrievalThe Generic notification indicator parameter field shall be coded as shown in Table 2-1.TABLE 2-1/Q.733Coding of the Generic notificatio
20、n indicator parameterThe Generic notification indicator parameter is accompanied by the parameter compatibility information parameter. Theprocedures for the compatibility are defined in 2.9.5/Q.764.2.5 Signalling requirements2.5.1 Activation/deactivation/registrationNot applicable.2.5.2 Invocation a
21、nd operation2.5.2.1 Actions at the originating local exchangeThe originating local exchange is the exchange where the service is controlled. The originating local exchange for thisdescription is not necessarily the originating exchange for the basic call.Bits7 6 5 4 3 2 1Description1 1 1 1 0 0 11 1
22、1 1 0 1 0Remote holdRemote retrievalRecommendation Q.733 (03/93) 32.5.2.1.1 Normal operation2.5.2.1.1.1 Hold requestWhen a call is placed on hold, or when a hold notification is received from the access signalling system, a notification isconveyed in a CPG message towards the remote user, indicating
23、 that the call has been placed on hold.The CPG message shall only be sent after the ACM has been received.2.5.2.1.1.2 Retrieve requestWhen a call that was placed on hold is retrieved, or when a retrieve notification is received from the access signallingsystem, a notification is conveyed in a CPG me
24、ssage towards the remote user, indicating that the call has been retrieved.2.5.2.1.2 Exceptional proceduresNo exceptional procedures are identified.2.5.2.2 Actions at the transit exchange2.5.2.2.1 Normal operationA transit exchange shall transfer the notification indication to the succeeding exchang
25、e.2.5.2.2.2 Exceptional proceduresNo exceptional procedures are identified.2.5.2.3 Actions at the outgoing international gateway exchange2.5.2.3.1 Normal operationAn outgoing international gateway exchange shall transfer the notification indication to the succeeding exchange.2.5.2.3.2 Exceptional pr
26、oceduresNo exceptional procedures are identified.2.5.2.4 Actions at the incoming international gateway exchange2.5.2.4.1 Normal operationAn incoming international gateway exchange shall transfer the notification indication to the succeeding exchange.2.5.2.4.2 Exceptional proceduresNo exceptional pro
27、cedures are identified.2.5.2.5 Actions at the destination local exchangeThe destination local exchange for this description is not necessarily the destination exchange for the basic call.2.5.2.5.1 Normal operationAt the exchange where user B is connected, the notification indication contained in the
28、 CPG message is passed on to theaccess signalling system of user B.2.5.2.5.2 Exceptional proceduresNo exceptional procedures are identified.4 Recommendation Q.733 (03/93)2.6 Interactions with other supplementary services2.6.1 Call waiting (CW)No impact on ISUP.2.6.2 Call transfer servicesNo applicab
29、le interaction at this time.2.6.3 Connected line identification presentation (COLP)No impact on ISUP.2.6.4 Connected line identification restriction (COLR)No impact on ISUP.2.6.5 Calling line identification presentation (CLIP)No impact on ISUP.2.6.6 Calling line identification restriction (CLIR)No i
30、mpact on ISUP.2.6.7 Closed user group (CUG)No impact on ISUP.2.6.8 Conference calling (CONF)No impact on ISUP.2.6.9 Direct dialling in (DDI)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 forwarding no reply
31、(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.Recommendation Q.733 (03/93) 52.6.13 User-to-user signalling (UUS)No impac
32、t 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 service 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 ap
33、plicable.2.6.16 Advice of charge (AOC)No impact on ISUP.2.6.17 Sub-addressing (SUB)No impact on ISUP.2.6.18 Terminal portability (TP)No impact on ISUP.2.6.19 Completion of calls to busy subscriber (CCBS)No applicable interaction at this time.2.6.20 Malicious call identification (MCID)No impact on IS
34、UP.2.6.21 Reverse charging (REV)No applicable interaction at this time.2.6.22 Multi-level precedence and preemption (MLPP)No impact on ISUP.2.6.23 Private numbering plan (PNP)No applicable interaction at this time.2.6.24 International telecommunication charge cardNo applicable interaction at this ti
35、me.2.7 Interaction with other networksIn the case of interaction with PSTN, it is a network provider option to supply the remote user with an in-bandindication.In the case of interactions with networks which do not provide the notification procedure, the interworking exchangewill discard the CPG mes
36、sage containing the notification indication. The call will then be completed according to thebasic call procedure as described in Q.764.6 Recommendation Q.733 (03/93)2.8 Signalling flowsExamples of information flow for the CALL HOLD supplementary service are shown in Figure 2-1 and Figure 2-2.2.9 Pa
37、rameter values (timers)No specific timers are required.NOTE In the case of Hold during waiting for answer, if Tg (the Awaiting Answer Timer, see Annex A/Q.764) expires,the call will be released according to the basic call procedure.2.10 Dynamic descriptionNo dynamic descriptions (SDLs) are required.
38、T1135890-91/d01IAM IAMACMACMCPG CPGCPGCPGUser AOriginatinglocal exchangeTransitexchangeDestinationlocal exchange User BSET-UPALERTINGHOLDHOLD ACKRETRIEVERETRIEVE ACKSET-UPALERTINGNOTIFYNOTIFY(held) (held)(retrieve) (retrieve)(held)(retrieve)IAMACMCPGInitial address messageAddress complete messageCal
39、l progress mes sageFIGURE 2-1/Q.733Hold and retrieve during waiting for answerFIGURE 2-1/Q.733.D01 = 15.5 CMRecommendation Q.733 (03/93) 7CPG CPGCPG CPGT1135900-91/d02User ADestinationlocal exchangeOriginatinglocal exchangeTransitexchange User BHOLDHOLD ACK RETRIEVERETRIEVE ACKNOTIFYNOTIFY(held)(ret
40、rieve)(held)(retrieve)(held)(retrieve)ACTIVE CALL (A B)FIGURE 2-2/Q.733Hold and retrieve during active phaseFIGURE 2-2/Q.733.D02 = 12.5 CM4 Terminal Portability (TP)4.1 DefinitionThe Terminal Portability supplementary service allows a user to move a terminal from one socket to another withinone give
41、n basic access during the active state of the call. It also allows a user to move a call from one terminal to anotherterminal within one given basic access during the active phase of the call.4.2 Description4.2.1 General descriptionBy requesting a Suspend/Resume procedure the calling as well as the
42、called user is enabled to move the terminal bymeans of unplugging and reconnecting it.In addition to that it is possible to replace the terminal by another compatible one or to suspend and resume a callwithout changing the terminal or the socket.8 Recommendation Q.733 (03/93)The stage 1 definition f
43、or the Terminal Portability supplementary service is given in Recommendation I.253.4. Thestage 2 description is given in Recommendation Q.85.4. The stage 3 DSS 1 description is given in Recommenda-tion Q.953.4. This stage 3 description of terminal portability supplementary service uses the ISDN User
44、 Part protocol asdefined in Recommendations Q.761-Q.764 and Q.766.4.2.2 Specific terminologyServed user: The user sending Suspend and Resume.Suspend: Message sent to suspend a call.Resume: Message sent to resume a call.4.2.3 Qualification on the applicability to telecommunication servicesSee Recomme
45、ndation I.253.4.4.2.4 State definitionsNo specific state definitions are required.4.3 Operational requirements4.3.1 Provision/withdrawalSee Recommendation I.253.4.4.3.2 Requirements on the originating network sideNot applicable.4.3.3 Requirements in the networkNo specific requirements are needed in
46、the network.4.3.4 Requirements on the terminating network sideNot applicable.4.4 Coding requirementsFor the Terminal Portability supplementary service the Suspend and Resume messages containing the Suspend/Resumeindicators set to “ISDN subscriber initiated” are used.4.5 Signalling requirements4.5.1
47、Activation/deactivation/registrationNot applicable.4.5.2 Invocation and operation4.5.2.1 Actions at the originating local exchange4.5.2.1.1 Normal operationThe Suspend message indicates a temporary cessation of communication without releasing the call. It can only beaccepted during the conversation/
48、data phase. A Suspend message can be generated in response to a Suspend requestfrom the calling or called party.Recommendation Q.733 (03/93) 9A Resume message indicates a request to recommence communication. A request to release the call received from thecalling or called party will override the Sus
49、pend/Resume sequence and the procedure for normal call release as describedin 2.3/Q.764 will be followed.a) Terminal Portability requested by the calling partyOn receipt of a suspend request from the calling party, the originating local exchange sends a Suspendmessage to the succeeding exchange.Because the suspend controlling exchange is always located in the network of the Suspend initiating userthe originating local exchange is the Suspend controlling exchange for this case and starts Timer T2 toensure the receipt of a Resume reques
