1、INTERNATIONAL TELECOMMUNICATION UNION)45G134 1 TELECOMMUNICATION (03/93)STANDARDIZATION SECTOROF ITU30%#) each ISDN member of a CUG isidentified by an ISDN number.The Closed User Group (CUG) supplementary service enables a group of users to intercommunicate only amongthemselves or, as required, one
2、or more users may be provided with incoming/outgoing access to users outside the group.The stage 1 definition of the CUG service is given in Recommendation I.255. The stage 2 description including networkfunctions are given in Recommendation Q.85.1, and the stage 3 DSS 1 description is given in Reco
3、mmendation Q.955.1.This stage 3 description of the CUG uses the ISDN User Part protocol as defined in Recommendations Q.761-Q.764 andQ.730.The realization of the CUG facilities is done by the provision of interlock codes and is based on various validationchecks as defined in Recommendation Q.85 at c
4、all set-up, determining whether or not a requested call to or from a userhaving a CUG facility is allowed. In particular, a validation check is performed by verifying that both the calling andcalled parties belong to the CUG indicated by the interlock code.The data for each CUG that a user belongs t
5、o can either be stored at the local exchange to which the user is connected(decentralized administration of CUG data), or at dedicated point(s) in the network (centralized administration of CUGdata).In 1.5.2.1.1 i) the call set-up procedure based on decentralized administration of CUG data is specif
6、ied making use of theISDN User Part as defined in Recommendations Q.761-764 and Q.766.In 1.5.2.1.1 ii) the call set-up procedure based on centralized administration of CUG data is specified making use of theISDN User Part as defined in Recommendations Q.761-764, Q.766 and Q.767 and the Transaction C
7、apabilities (TC) asdefined in Recommendations Q.771-775.In 1.5.2.1.1 ii) the application service element (ASE) on top of Transaction Capabilities for CUG validation check withcentralized administration of CUG data is specified.1.2.2 Specific terminologyCUG: Closed User Group.Calling Party Number is
8、the network (e.g. E.164) number of the calling party.Called Party Number is the network (e.g. E.164) number of the called party.2 Recommendation Q.735 (03/93)CUG Interlock Code is the code to uniquely identify a CUG inside the network.Called User Index is the local index at the called user to identi
9、fy a particular CUG he belongs to.CMC: CUG Management Centre1.2.3 Qualification on the applicability to telecommunication servicesNot applicable.1.2.4 State definitionsNo specific state definitions are required.1.3 Operational requirements1.3.1 Provision/withdrawalSee Recommendation I.255.1.1.3.2 Re
10、quirements on the originating network sideNot applicable.1.3.3 Requirements in the networkNo specific network requirement identified.1.3.4 Requirements on the terminating network sideNot applicable.1.4 Coding requirementsClause 3/Q.763 gives the coding for the Closed User Group interlock code and th
11、e Optional forward call indicatorparameters which are required to support this service.See Tables 1-1 through 1-10.TABLE 1-1/Q.735Action at the gateway with a network without CUG capabilityCUG call indicator in IAM Action at the gateway exchangeCUG without outgoing access Release the call with cause
12、 #29CUG with outgoing access Treat the call as an ordinary calla)Non-CUG Treat the call as an ordinary calla)Discard the interlock code parameter and change the CUG call indicator of the optional forward call indicator to non-CUGcall or discard the whole parameter if appropriate.Recommendation Q.735
13、 (03/93) 3TABLE 1-2/Q.735Handling of a CUG call at the destination exchangeClass of called userCUG call indicator inIAMCUG match check CUG CUG+IA No CUGNo ICB ICB No ICB ICBCUG with OA notallowedMatch CUG call Release cause #55 CUG call Release cause #55 Release the callwith cause #87No match Releas
14、e the call with cause #87 Release the call with cause #87CUG with OAallowedMatch CUG call Release cause #55 CUG+OAcallNon-CUG callNon-CUG callNo match Release the call with cause #87 Non-CUG callNon-CUG Release the call with cause #87 Non-CUG call Non-CUG callIA Incoming accessOA Outgoing accessICB
15、Incoming calls barredMatch called The interlock code in the received IAM matches one of the CUGs to which the user belongs.No match The interlock code does not match any of the CUGs to which the called user belongs.NOTE As OA attribute of the called user is of no concern at the destination exchange,
16、 CUG+OA class is equivalent to CUG, andCUG+IA class is equivalent to CUG+IA in this table. Subscription of preferential CUG by the called user is also of no concern inthis table.4 Recommendation Q.735 (03/93)TABLE 1-3/Q.735Validation check of CUG call concerning the calling userIndication from calli
17、ng userCalling user classCUG call with index CUG+OA call withindexCUG call withoutindexCUG+OA callwithout indexNon-CUG callCUG without pref. CUG call (*1) (*3)IC: spec. CUGCUG call (*1) (*3)IC: spec. CUGReturn Error cause#62Return Error cause#62Return Errorcause #62CUG+OAEwithout pref.CUG call (*1)
18、(*3)IC: spec. CUGCUG+OA (*2) (*3)IC: spec. CUGReturn Error cause#62Non-CUG call Return Errorcause #62CUG+OAIwithout pref.CUG+OA (*2) (*3)IC: spec. CUGCUG+OA (*2) (*3)IC: spec. CUGNon-CUG call Non-CUG call Non-CUG callCUG with pref. CUG call (*1) (*3)IC: spec. CUGCUG call (*1) (*3)IC: spec. CUGCUG (*
19、4) callIC: pref. CUGReturn Error cause#62CUG callIC: pref. CUG (*4)CUG+OAE withpref.CUG call (*1) (*3)IC: spec. CUGCUG+OA (*2) (*3)IC: spec. CUGCUG (*4)IC: pref. CUGNon-CUG call CUG call (*4)pref. CUGCUG+OAI withpref.CUG+OA(*1) (*2) (*3)IC: spec. CUGCUG+OA(*2) (*3) (*1)IC: spec. CUG(*4) (*5) CUG+OA
20、(*1) (*4)IC: pref. CUG(*4) (*5)No CUG Return Errorcause #50Return Error #50 Return Error #50 Return Error #50 Non-CUG callOAE Outgoing access, explicit request required.OAI Outgoing access, implicit outgoing access for all calls.IC Interlock code of the CUG selected.NOTE As IA (incoming access) attr
21、ibute of the calling user is of no concern for this validation check, CUG+OA/IA is equivalentto CUG+OA in this table.(*1) In case of OCB (outgoing calls barred) within the Error with cause #53.(*2) In case of OCB within the CUG, the call is interpreted as a non-CUG call.(*3) In case the specified in
22、dex does not match any of the registered indices, Return Error with cause #90.(*4) In the case of OCB within the CUG, this combination is not allowed.(*5) Both “Preferential CUG” and “implicit” outgoing access options imply that no subscriber procedures are needed toinvoke either options when placin
23、g a call. When a user subscribes to both options, the network does not know whichoption the user is invoking, if no additional procedures are used when placing the call. Then one of the followingoperations are recommended:a) if no information is given, the preferential CUG will be assumed;b) the net
24、work will route the call with preferential CUG with outgoing access. The call will therefore be connected ifthe called access is: a member of preferential CUG; or a member of another CUG with incoming access; or a non-CUG user.Recommendation Q.735 (03/93) 5TABLE 1-4/Q.735Validation check of CUG call
25、 concerning the called userClass of called userCUG call ind. inIAMCUG matchcheckCUG CUG+IANo ICB ICB No ICB ICBCUG with OAnot allowedMatch CUG call Return Errorcause #55CUG call Return Errorcause #55Return Error withcause #87No match Return Error with cause #87 Return Error with cause #87CUG with OA
26、Match CUG call Return Errorcause #55CUG+OA call Non-CUG callNon-CUG callallowedNo match Return Error with cause #87 Non-CUG callNon-CUG Return Error with cause #87 Non-CUG call Non-CUGMatch The interlock code in the receive IAM matches one of the CUGs the called user belongs to.No match The interloc
27、k code does not match any of the CUGs the called user belongs to.NOTES1 As OA (outgoing access) attribute of the called user is of no concern at the destination exchange, CUG+OA class isequivalent to CUG and CUG+OA/IA class is equivalent to CUG+IA in this table.Subscription of preferential CUG by th
28、e called user is also of no concern in this table.2 The ASN.1 information for the centralized CUG service is contained in Appendix I.6 Recommendation Q.735 (03/93)TABLE 1-5/Q.735Parameters of operations and outcomesCUG Check 1CUG Check 1 Timer = 5-10 sec Class = 1 Code = 00000001Parameters with Invo
29、ke Opt/Man ReferenceCallingUserIndex O 10.10CUGCallIndicator M 10.20CallingPartyNumber M 10.30BearerCapability M 10.90HighLayerCompatibility O 10.10Parameters with Return ResultCUGInterlockCode O 10.5CUGCallIndicator M 10.2Linked OperationsNot applicableErrorsUnsuccessfulCheck 10.7NOTES1 The Calling
30、PartyNumber (10.3) is the network (e.g. E.164) number of the calling party. It is expressed in the samemanner as the ISUP Calling party number in 3.8/Q.763. The code of this parameter is “10000011”.2 The CUGInterlockCode (10.5) is the code to uniquely identify a CUG inside the network. It is express
31、ed in the samemanner as the ISUP CUG interlock code in 3.13/Q.763. The code of this parameter is “10000101”.3 The BearerCapability (10.9) is expressed in the same manner as the Bearer capability information element (octets 3 =G0)-0,)#)4G0,OCAL)NDEX,OCAL)NDEX G0).4%2G0 G0 G0 G9G13G13G0G03OMEG0NETWORK
32、SG0MAYG0SPECIFYG0AG0MAXIMUMG0VALUEG0OFG0THEG0#5G0)NDEXG0FROMG0 G0TOG0 CUGCallIndicator Code=10000010Contents Meaning00000000 Non-CUG call00000001 Non-CUG call00000010 CUG call with outgoing access00000011 CUG call without outgoing accessNOTE The CUGCallIndicator (10.2) indicates whether the call is
33、requested or designated as a CUG call and whether outgoingaccess is requested or allowed.#5#ALL)NDICATOR G0G0; =G0)-0,)#)4G0#ALL)NDICATOR#ALL)NDICATOR G0G0).4%2 G0.ON#5#ALLG0G0 G9 .ON#5#ALLG0G0 G9 OUTGOING!CCESS!LLOWED#5#ALLG0 G9 OUTGOING!CCESS.OT!LLOWED#5#ALLG0 G9G0Recommendation Q.735 (03/93) 9TAB
34、LE 1-9/Q.735ErrorsTABLE 1-10/Q.735CauseUnsuccessfulCheck Code = 00000001ParametersCause 10.85NSUCCESSFUL#HECK %RROR0!2!-%4%23 G0#AUSEG0G0 Cause Code = 10000111 Contents binary (decimal) Meaning00110010 (50)00110101 (53)00110111 (55)00111110 (62)01011010 (90)01010111 (87)01011000 (88)01101111 (111)Re
35、quested facility not subscribedOutgoing calls barred within CUGIncoming calls barred within CUGInconsistencyInDesignatedOutgoingAccessInformationAndSubscriberClassNon-existent CUGUser not member of CUGIncompatible destinationProtocol error, unspecifiedNOTE The Cause indicates the reason why the CUG
36、check is unsuccessful.#AUSE G0 =G0)-0,)#)4G0#AUSE#ODE#AUSE#ODE G0).4%2 G02EQUESTED in addition, there is a need for a CUG identification mechanism that would be accepted by all of theencompassed networks. One such mechanism presently exists for CUGs spanning over data networks having X.121 asthe num
37、bering plan (see Recommendation X.180, Administrative Arrangements for International Closed User Groups).An equivalent mechanism should be defined for CUGs on networks using the E.164 numbering plan, or on networkswhich do not use the same numbering plan.1.8 Signalling flowsFigure 1-1 for the decent
38、ralized CUG service.FIgures 1-2 to 1-4 for the centralized CUG service.16 Recommendation Q.735 (03/93)T1130060-91/d01OriginatinguserOriginatingexchangeTransitexchangeTerminatingexchangeTerminatinguserSetupCall proceeding(1)a)IAMb)IAMb)SetupAlertingConnectSetupCall proceedingDisconnectReleaseRelease
39、completeACMCPG (alerting)RLCACMCPG (alerting)ANMANMIAMb)RELc)IAMb)RLCAlertingConnect informationConnect acknowledgeAG9G0G03UCCESSFULG0ESTABLISHMENTG0OFG0AG0#5G0CALLBG9G0G05NSUCCESSFULG0ESTABLISHMENTG0OFG0AG0#5G0CALL( ) Indicates exchange functions. These are described below Figure 1-2.IAM contains t
40、he interlock code and CUG call indication, possibly with outgoing access.REL contains the cause parameter to indicate why the call is being released.a)b)c)FIGURE 1-1/Q.735Decentralized operation of CUGRELc)OETEDEIAMCPGANMACMOriginating exchangeTransit exchangeDestination exchangeInitial address mess
41、ageCall progressAnswer messageAddress complete message(2)(3)(3)(2)Recommendation Q.735 (03/93) 17T1130070-91/d02OriginatinguserOriginatingexchangeTransitexchangeTerminatingexchangeTerminatinguserSetupCall proceeding(4)a)IAMb)AlertingConnectACMCPG (alerting)CPG (alerting)FIGURE 1-2/Q.735Centralized o
42、peration of CUG(5)CMCACMCbI CUG check 1RR check resultNetworkboundaryANMANMACMConnectConnectAcknowledgeAlertingSetupIAMb)I CUG check 2(6)ACMRR check result(7)CPG (alerting)ANMIAMb)CMCIRRCUG management centerInvokeReturn resultValidation check on whether the requested call is allowed to the calling u
43、ser. based on the data stored at the originating exchange.In the case of an international gateway exchange, interlock code conversion if the national network is not using international interlock codes. Validation check on whether the requested call is allowed to the called user, based on the data st
44、ored at the destination exchange. Check if the calling user subscribes to the CUG service.Check of the result of the validation check performed in a CMC.Check if the called user subscribes to the CUG service.Check of the result of the validation check performed in a CMC.a)b)(1)(2)(3)(4)(5)(6)(7)( )
45、Indicates exchange functions. These are described below. IAM contains the interlock code, CUG call indication possibly with outgoing access.TransitexchangeNOTE Example message flow for a CUG call with centralized administration of CUG data.18 Recommendation Q.735 (03/93)T1130080-91/d03Originatingexc
46、hange CMC CMCASE TCAP TCAP ASE ASE TCAP TCAP ASETC-INVOKE req.(CUG Check 1,class = 1)TC-BEGIN req.TC-END ind.TC-RESULT ind.TC-BEGIN ind.TC-INVOKE ind.TC-RESULT req.TC-END req.TC-U-ERROR ind.TC-U-ERROR req.FIGURE 1-3/Q.735Primitive flows between ASE and TCAP for CUG Check 1AG9G0G03UCCESSFULG0CASE BG9
47、G0G05NSUCCESSFULG0CASEOriginatingexchangeTC-INVOKE req.(CUG Check 1,class = 1)TC-BEGIN req. TC-BEGIN ind.TC-INVOKE ind.TC-END ind.TC-END req.Recommendation Q.735 (03/93) 19T1130090-91/d04Terminatingexchange CMC CMCASE TCAP TCAP ASE ASE TCAP TCAP ASETC-INVOKE req.(CUG Check 2,class = 1)TC-BEGIN req.T
48、C-END ind.TC-RESULT ind.TC-BEGIN ind.TC-INVOKE ind.TC-RESULT req.TC-END req.TC-BEGIN req.TC-END ind.TC-U-ERROR ind.TC-BEGIN ind.TC-INVOKE ind.TC-U-ERROR req.TC-END req.FIGURE 1-4/Q.735Primitive flows between ASE and TCAP for CUG Check 2AG9G0G03UCCESSFULG0CASE BG9G0G05NSUCCESSFULG0CASETerminatingexch
49、angeTC-INVOKE req.(CUG Check 2,class = 1)1.9 Parameter value (timers)No specific timers are required.1.10 Dynamic description (SDLs)See Figures 1-5 through 1-8.20 Recommendation Q.735 (03/93)FAT1130100-91/d05IdleSet-uprequestCheck-user-A-profileOutgoing-callSee basiccall processSee basiccall processSet causevalueCheck-B-rejCheck-user-B-profileIncoming-callActive IdleCheck-A-confOut-call-rejOut-call-confCheck-B-confInc-call-rejInc-call-confFIGURE 1-5/Q.735Closed user groupCheck -A-rejSee basiccall processRecommendati
