This Recommendation defines the stage 2 of the integrated services digital network (ISDN) as provided by telecommunications operators for the Closed User Group (CUG) supplementary service. Stage 2 identifies the functional capabilities and the information flows needed to support the service description. The Stage 2 description also identifies user operations not directly associated with a call (see Recommendation I.130 [1]).
ITU-T Q.85.1 FRENCH-1992 Referenced Document
ITU-T I.130-1988 METHOD FOR THE CHARACTERIZATION OF TELECOMMUNICATION SERVICES SUPPORTED BY AN ISDN AND NETWORK CAPABILITIES OF AN ISDN
ITU-T I.255.1 Closed User Group (Study Group I) 17 pp
ITU-T Q.763 Signalling System No. 7 - ISDN User Part Formats and Codes - Series Q: Switching and Signalling - Specifications of Signalling System No. 7 - ISDN User Part (Study Group 11)*， 1999-12-01 Update
ITU-T Q.931 ISDN user-network interface layer 3 specification for basic call control Study Group 11*， 1998-05-01 Update
ITU-T Q.950 Supplementary Services Protocols Structure and General Principles Series Q: Switching and Signalling Digital Subscriber Signalling System No.1 - Stage 3 Description for Supplementary Services Using DSS 1 Study Group 11*， 2000-06-01 Update
ITU-T Q.85.1 FRENCH-1992 history
1992ITU-T Q.85.1 FRENCH-1992 STAGE 2 DESCRIPTION FOR COMMUNITY OF INTEREST SUPPLEMENTARY SERVICES SECTION 1 - CLOSED USER GROUP (CUG)