Table of Contents
1ClosedUserGroup(CUG)
1.1Scope
1.2References
1.3Definitions
1.4Abbreviations
1.5Description
1.6Operationalrequirements
1.6.1Provisionandwithdrawal
1.6.2Requirementsontheoriginatingnetwork
side
1.6.3Requirementsonthedestinationnetwork
side
1.7Codingrequirements
1.7.1Messagesandclosedusergroupinformation
element
1.7.2Causeinformationelement
1.8Primitiveandstatedefinitions
1.8.1Primitivedefinitions
1.8.2Statedefinitions
1.9SignallingproceduresatthecoincidentSBandTB
referencepoint
1.9.1Activation,deactivationandregistration
1.9.2Invocationandoperation
1.10ProceduresattheTBreferencepointforinterworking
withprivateB-ISDNs
1.11ProceduresforinterworkingbetweentheDSS1andthe
DSS2protocol
1.12Interactionswithothernetworks
1.13Interactionswith(other)supplementaryservices
1.13.1Connectedlineidentificationpresentation
1.13.2Connectedlineidentificationrestriction
1.13.3Callinglineidentificationpresentation
1.13.4Callinglineidentificationrestriction
1.13.5ClosedUserGroup
1.13.6DirectDialling_In
1.13.7User-to-usersignalling
1.13.8Multiplesubscribernumber
1.13.9Sub-addressing
1.14Parametervalues
1.15Dynamicdescription(SDL)
1.15.1Theclosedusergroupprocess
1.15.2Relationtobasiccall/connectioncontrol
AnnexASymmetricoperation
AnnexBProtocolextensionstothisRecommendationfor
calls/connectionsusingtheproceduresof
RecommendationQ.2971[13] Abstract
Defines the DSS 2 signalling protocol for supporting the CUG supplementary service in B-ISDN, for use at the TB and coincident SB and TB reference point, which allows users to form groups to and from which access is restricted. Group members are able to communicate between themselves, but not normally with users outside the group. Certain members may have additional capabilities allowing them to originate calls to destinations outside the group, and/or to receive calls from outside the group, or have restrictions preventing them from originating or receiving call from other members of CUG.
