1、INTERNATIONAL TELECOMMUNICATION UNION)45G134 1 TELECOMMUNICATION (03/93)STANDARDIZATION SECTOROF ITU%.%2!,G0G02%#/-%.$!4)/.3/.G0G04%,%0(/.%G0G037)4#().!.$G0G03).!,).modified at Helsinki, 1993)2 Call forwarding2.1 ScopeThis Recommendation defines the Stage 2 for the Call Forwarding supplementary serv
2、ices (CFB, CFNR, CFU) ofIntegrated Services Digital Network (ISDN) as provided by public telecommunications operators. Stage 2 identifies thefunctional capabilities and the information flows needed to support the service description. The Stage 2 description alsoidentifies user operations not directl
3、y associated with a call (see Recommendation I.130 1).This Recommendation is specified according to the methodology specified in Recommendation Q.65 2.This Recommendation does not formally describe the relationship between this supplementary service and the basic call,but where possible this informa
4、tion is included for guidance.In addition, this Recommendation does not specify the requirements where the service is provided to the user via aprivate ISDN. This Recommendation does not specify the requirements for the allocation of defined functional entitieswithin a private ISDN; it does however
5、define which functional entities may be allocated to a private ISDN.This Recommendation does not specify the additional requirements where the service is provided to the user via atelecommunications network that is not an ISDN.This Recommendation describes the three versions of Call Forwarding suppl
6、ementary services, when implemented usingthe “forward switching” network routing algorithm and partial rerouting at the public/private network interface ascontained in Recommendation Q.80 3.The description of full rerouting as described in Recommendation Q.80 is outside the scope of this Recommendat
7、ion.The procedures for the activation/deactivation/registration of the forwarding services are contained in Annex B.The CFU supplementary service permits a served user to have the network send to another number all incoming calls forthe served users number (or just those associated with a specified
8、basic service). The served users originating service isunaffected. If this service is activated, calls are forwarded no matter the condition of the termination.The CFB supplementary service permits a served user to have the network send to another number all incoming calls forthe served users number
9、 (or just those associated with a specified basic service) which meet busy at the served usersISDN number. The served users originating service is unaffected.The CFNR supplementary service permits a served user to have the network send to another number all incoming callsfor the served users number
10、(or just those associated with a specified basic service) which meet no reply at the servedusers ISDN number. The served users originating service is unaffected.The forwarded-to number is registered with the network for use on all calls.2 Recommendation Q.82 (03/93)This Recommendation is applicable
11、to the Stage 3 Recommendations for the ISDN Forwarding supplementary servicesCFB, CFNR and CFU. The term “Stage 3” is also defined in Recommendation I.130 1. Where the text indicated thestatus of a requirement, i.e. as strict command or prohibition, as authorization leaving freedom, as a capability
12、orpossibility, this shall be reflected in the text of the relevant Stage 2 and Stage 3 Recommendations.Furthermore, conformance to this Recommendation is met by conforming to the Stage 3 Recommendations with the fieldof application appropriate to the equipment being implemented. Therefore no method
13、of testing is provided for thisRecommendation.2.2 ReferencesThis Recommendation incorporates by dated or undated reference, provisions from other publications. These referencesare cited at the appropriate places in this Recommendation and the publications are listed hereafter. For dated references,s
14、ubsequent amendments to, or revisions of any of these publications apply to this Recommendation only whenincorporated in it by amendment or revision. For undated references, the latest edition of the publication referred toapplies.1 CCITT Recommendation I.130 Method for the characterization of telec
15、ommunication services supported anISDN and network capabilities of an ISDN, 1988.2 CCITT Recommendation Q.65 Stage 2 of the method for the characterization of services supported byISDN, 1988.3 CCITT Recommendation Q.80 Introduction to stage 2 service descriptions for supplementary services, 1988.4 C
16、CITT Recommendation Q.71 ISDN 64 kbit/s circuit mode switched bearer service, 1992.5 CCITT Recommendation I.112 Vocabulary of terms for ISDNs, 1988.6 CCITT Recommendation E.164 Numbering plan for the ISDN era, 1988.7 CCITT Recommendation I.252.2 Call Forwarding Busy (CFB), 1992.8 CCITT Recommendatio
17、n I.252.3 Call Forwarding No Reply (CFNR), 1992.9 CCITT Recommendation I.252.4 Call Forwarding Unconditional (CFU), 1992.2.3 DefinitionsFor the purposes of this Recommendation, the following definitions apply:Integrated Services Digital Network (ISDN): See 2.3/I.112 5, definition 308.Service - telec
18、ommunications service: See 2.2/I.112 5, definition 201.ISDN number: A number conforming to the numbering plan and structure specified in Recommendation E.164 6.originally called number: The number of the B1-party.connected number: The number of the final destination (C-party).forwarding number: The
19、number of the served user, i.e. the subscriber who initiates the forwarding service and fromwhere the call has been forwarded.forwarded-to number (FTN): The number to which a call has been forwarded.forwarding indicator (FI): Indicator showing that a call has been forwarded and indicating whether th
20、is informationshould be given to the calling party.forwarding indication: Indication for the served user that forwarding has occurred.presentation indicator (PI): Indicator showing whether the FTN should be presented to the calling user, as derivedfrom the C-partys COLR supplementary service.Recomme
21、ndation Q.82 (03/93) 3forwarding cause: Parameter which contains the reason for the forwarding, e.g. CFU, CFB, CFNR, CD.network facility indicator (NFI): Indicator showing the preferred transit network or a network specific facility to beused for forwarding.2.4 Symbols and abbreviationsAbbreviations
22、 used:BC Basic CallCC Call ControlCCA Call Control AgentCD Call DeflectionCFB Call Forwarding on BusyCFNR Call Forwarding No ReplyCFPC Call Forwarding Profile ControlCFU Call Forwarding UnconditionalFC Forwarding CauseFE Functional EntryFI Forwarding IndicatorFTN Forwarded-to NumberGD Global DataLE
23、Local ExchangeNDUB Network Determined User BusyNFI Network Facility IndicatorNSO Notification Subscription OptionPI Presentation IndicatorPN Private NetworkPNX Private Network ExchangeSCE Service Control EntitySCM Service Control ModelTE Terminal EquipmentUDUB User Determined User Busy2.5 Descriptio
24、nThe general description of the CFB supplementary service is specified in I.252.2 7.The general description of the CFNR supplementary service is specified in I.252.3 8.The general description of the CFU supplementary service is specified in I.252.4 9.4 Recommendation Q.82 (03/93)2.6 Derivation of th
25、e functional model2.6.1 Functional model descriptionThe functional model for the CF supplementary service is shown in Figure 2-1.NOTE The addition of the functional model for the activation/deactivation/registration of the forwarding services iscontained in Figure B.2-1.T1126410-90/d01FE1 FE2 FE3 FE
26、4 FE5FE7 FE8FE6raarbbrccrddreerffrggFIGURE 2-1/Q.82Functional modelFIGURE 2-1/Q.82.D01 = 7 cm2.6.2 Description of the functional entitiesThe functional entities required by the CF supplementary service in addition to those of the basic call are as follows:FE1: Callers service agentFE2: Callers servi
27、ce control entityFE3: Call forwarding execution entityFE4: Call forwarding detection and control entityFE5: Served users service agentFE6: Interface controlling entityFE7: Forwarded-to users service control entityFE8: Forwarded-to users service agent2.6.3 Relationship with a basic serviceThe relatio
28、nship with a basic service is shown in Figure 2-2.NOTE The relationship in Figure 2-3 covers scenarios 8 and 9 in 2.10.2.7 Information flows2.7.1 Information flows diagramThe information flows for the Call Forwarding supplementary service are shown in Figures 2-4 to 2-12.Recommendation Q.82 (03/93)
29、5T1132530-91/d02FE1 FE2 FE3 FE4 FE5CCA CC CC CC CC CCACCFE6 FE7 FE8CC CC CCAC-partyB-partyA-partyraarbbrccrddr11r22r22r33rffrggr22FIGURE 2-2/Q.82Relationship with a basic servicer33r22r22r22reeFIGURE 2-2/Q.82.D02 = 10.5 cmT1132540-91/d03FE1 FE2 FE3 FE4 FE5CCA CC CC CC CCFE6 FE7CCFE8CCAB-partyC-party
30、A-partyraarbbrddr11r22r22r22r22rggr33FIGURE 2-3/Q.82reeFIGURE 2-3/Q.82.D03 = 10.5 cm6Recommendation Q.82 (03/93)921940945948949935932939938943933931922911936934963964930923911T1144110-92/d0493A94A951972974971975966967981431231 231/241221 231 231 241 241 251241 251241 251FE1 FE2 FE3 FE4 FE5 FE6/7 FE8
31、SETUP SETUP SETUPRELEASERELEASESETUPINFORM 5INFORM 6INFORM 7INFORM 6INFORM 2INFORM 1INFORM 10INFORM 11INFORM 3INFORM 4req. ind.req. ind.req. ind.req. ind.req. ind. req. ind.req. ind.req. ind.req. ind.req. ind.SETUP(reject)CAUSE UDUBreq. ind.req. ind.req. ind.req. ind.req. ind.req. ind.(al.)req. ind.
32、(Note 1)(Note 2)raarbbrccreerggNOTE The notes are found after Figure 2-12.rddreq. ind.FIGURE 2-4/Q.82Information flow of CFB, UDUBS E T U PREPORTFIGURE 2-4/Q.82.D04 = FIGURE LITALIANNERecommendation Q.82 (03/93)792194094194594893593293993894393393192291193693496396493092391194995193A9819749729759669
33、67971T1144120-92/d0594A221 231231 241431231 231/241241 251245 251FE1 FE2 FE3 FE4 FE5 FE6/7 FE8raarbbrccrddreerggINFORM 2INFORM 1INFORM 6INFORM 7INFORM 10INFORM 11RELEASEINFORM 3INFORM 4INFORM 6S E T U PINFORM 5(Note 2)SETUPREPORTSETUPSETUPRecognizeCFB invokedreq. ind.req. ind.req. ind.req. ind.req.
34、ind.req. ind.req. ind.req. ind.req. ind.req. ind.req. ind.req. ind.req. ind.req. ind.req. ind.(al.)req. ind.(Note 1)NOTE The notes are found after Figure 2-12.FIGURE 2-5/Q.82Information flow of CFB, NDUBFIGURE 2-5/Q.82.D05 = FIGURE LITALIANNE8Recommendation Q.82 (03/93)921940947947945948949935932938
35、933931922911936934 963964930923911937972974981975966967971T1144130-92/d0695193A94A943221 231231 241 241 251244 251231 231/241241 251244 251244244431FE1 FE2 FE3 FE4 FE5 FE6/7 FE8raarbbrccrddreerggSETUPSETUP SETUPSETUPREPORTINFORM 2INFORM 1INFORM 6INFORM 7RELEASEINFORM 10INFORM 11REPORTINFORM 3INFORM
36、4S E T U PREPORT (alerting)INFORM 6INFORM 5req. ind.req. ind.req. ind.req. ind.req. ind.req. ind.req. ind.req. ind.req. ind.(alerting)req. ind.req. ind.req. ind.req. ind.req. ind.req. ind.req. ind.(Note 1)(Note 2)STARTCFNR TimerCFNR TimerexpiresNOTE The notes are found after Figure 2-12.FIGURE 2-6/Q
37、.82CFNR, Option A, late releasereq. ind.(al.)FIGURE 2-6/Q.82.D06 = FIGURE LITALIANNERecommendation Q.82 (03/93)992194093593293894393393192291193693496396493092391194794793A94A972974975966967971T1144140-92/d07951981231 241 241 251244 251231 231/241241 251244 251945, 948, 949221 231431FE1 FE2 FE3 FE4
38、FE5 FE6/7 FE8raarbbrccreerddrggINFORM 2INFORM 7INFORM 1INFORM 6INFORM 11RELEASEREPORTINFORM 3INFORM 4S E T U PINFORM 6INFORM 5REPORTSETUPSETUPSETUPSETUPreq. ind.req. ind.req. ind.req. ind.req. ind.req. ind. req. ind.(alertIng)req. ind.req. ind.req. ind.req. ind.req. ind.req. ind.req. ind.req. ind.(a
39、l.)req. ind.(Note 1)(Note 2)INFORM 10STARTCFNR TimerCFNR TimerexpiresNOTE The notes are found after Figure 2-12.FIGURE 2-7/Q.82CFNR, Option B, early releasereq. ind.FIGURE 2-7/Q.82.D07 = FIGURE LITALIANNE10Recommendation Q.82 (03/93)92194093593293894393393192291193693496397497193092391194794793794A
40、951967966975T1144150-92/d0893A231 241221 231241 251244 251964972930241 251245 251431231FE1 FE2 FE3 FE4 FE5 FE6/7 FE8rggreerddrccrbbraaINFORM 2INFORM 7INFORM 1INFORM 6INFORM 10INFORM 11RELEASEINFORM 3INFORM 4S E T U PINFORM 6S E T U PINFORM 5SETUPSETUPSETUPSETUPSETUPREPORT(Note 1)req. ind.req. ind.re
41、sp. conf.resp. conf.req. ind.req. ind.req. ind.req. ind.req. ind.req. ind.req. ind.req. ind.(alerting)req. ind.req. ind.req. ind.req. ind.req. ind.req. ind.STARTCFNR TimerCFNR TimerexpiresNOTE The notes are found after Figure 2-12.FIGURE 2-8/Q.82CFNR, Option A, late release, C has automatic answerin
42、g equipment945, 948, 949FIGURE 2-8/Q.82.D08 = FIGURE LITALIANNERecommendation Q.82 (03/93)11940935932938943936934972947947937T1144160-92/d0993A94A95193D94E241 251241231221 231244 251963231/241231945, 948, 949FE1 FE2 FE3 FE4 FE5 FE6/7 FE8REPORTINFORM 10INFORM 11INFORM 13INFORM 3INFORM 4S E T U PRELEA
43、SE (cause NDUB)req. ind.req. ind.(alerting)req. ind.req. ind.req. ind.req. ind.req. ind.req. ind.req. ind.req. ind.(Note 3)SETUPSETUPSETUPraarbbrccrddreerggNOTE The notes are found after Figure 2-12.FIGURE 2-9/Q.82CFNR, Option A, late release, C-party NDUBSTARTCFNR TimerCFNR TimerexpiresFIGURE 2-9/Q
44、.82.D09 = FIGURE LITALIANNE12Recommendation Q.82 (03/93)94093593293894393696396494794793B93A94A951972974981T1144170-92/d1093A93A221 231241231241 251231245 251241 251FE1 FE2 FE3 FE4 FE5 FE6/7 FE8REPORTINFORM 10INFORM 11SETUPRELEASE (C-party)SETUPS E T U PINFORM 4INFORM 3INFORM 5SETUPSETUPSETUPSETUPre
45、q. ind.req. ind.req. ind.req. ind.req. ind.resp. conf.req. ind.req. ind.req. ind.resp. conf.req. ind.(alerting)req. ind.req. ind.req. ind.(Note 1)raarbbrccreerddrggSTARTCFNR TimerCFNR TimerexpiresNOTE The notes are found after Figure 2-12.945, 948, 949FIGURE 2-10/Q.82CFNR, Option A, late release, B-
46、party answers before receipt of alerting of the C-partyFIGURE 2-10/Q.82.D10 = FIGURE LITALIANNERecommendation Q.82 (03/93)1392194093593293993894393393192291193693496396493092391194A95193A972974975966967971981T1144180-92/d11221 231241231945, 948, 949431231241 251244 251231/241FE1 FE2 FE3 FE4 FE5 FE6/
47、7 FE8INFORM 2INFORM 7INFORM 1INFORM 6INFORM 10INFORM 11RELEASEINFORM 3INFORM 4S E T U PINFORM 6INFORM 5REPORTSETUPSETUPSETUPreq. ind.req. ind.req. ind.req. ind.req. ind.req. ind.req. ind.req. ind.req. ind.req. ind.req. ind.req. ind.req. ind.req. ind.(al.)req. ind.(Note 1)(Note 2)r aarbbr ccreerddrgg
48、RecognizeCFU invokedNOTE The notes are found after Figure 2-12.FIGURE 2-11/Q.82Information flow for CFUFIGURE 2-11/Q.82.D11 = FIGURE LITALIANNE14 Recommendation Q.82 (03/93)934936963964974981975971966T1144190-92/d12231 231231 241973972251241251244930FE3 FE6 FE7 FE8INFORM 4SETUPINFORM 4SETUPINFORM 6I
49、NFORM 6INFORM 5SETUPREPORTreq. ind.req. ind.req. ind.req. ind.req. ind.req. ind.req. ind.req. ind.(alerting)req. ind.rbbreerffrggFIGURE 2-12/Q.82Flows across the public/private network interface at C-party(Note 1)(Note 2)NOTES related to the Figures 2-4 to 2-12:1 The INFORM 5 shall be presented to FE8 not later than the associated SETUP req. ind.2 In case of: COLR temporary mode activated at C; or immediately responding terminal at C,the P
