0 Scope

03.853GPPClosed User Group (CUG) supplementary servicesStage 2TS

The present document gives the stage 2 description of the closed user group supplementary service.

The community of interest supplementary service defined is:

– closed user group (CUG) (see clause 1).

0.1 References

The following documents contain provisions which, through reference in this text, constitute provisions of the present document.

  • References are either specific (identified by date of publication, edition number, version number, etc.) or non‑specific.
  • For a specific reference, subsequent revisions do not apply.
  • For a non-specific reference, the latest version applies.
  • A non-specific reference to an ETS shall also be taken to refer to later versions published as an EN with the same number.
  • For this Release 1998 document, references to GSM documents are for Release 1998 versions (version 7.x.y).

[1] GSM 01.04: "Digital cellular telecommunications system (Phase 2+); Abbreviations and acronyms".

[2] GSM 02.85: "Digital cellular telecommunications system (Phase 2+); Closed User Group (CUG) Supplementary Services ‑ Stage 1".

0.2 Definitions

CUG terminology defined in GSM 02.85 is applicable to the present document. In addition, the following definitions apply.

CUG Authorisation Functions: Checks performed by the network to ensure that the integrity of a CUG related call is guarantied. CUG calls are rejected if they do not meet the criteria of these checks.

CUG call: A CUG call, in signalling terms, is a call where CUG information is passed from the originating switching entity to the destination entity.

CUG Index: A code used to select a CUG for an outgoing call, or to indicate an incoming CUG call. Indices are passed between the user and the network and have significance only within the context of a users subscription.

CUG Interlock Code: A code which uniquely identifies a CUG within a network. The Interlock code is passed from the point of origin to the destination in a CUG call to identify the CUG which has been invoked.

CUG Related Call Barring: CUG related call barring is call barring applied to a CUG subscriber by the home network when roaming in a non-CUG network. The user is unable to remove CUG related call barring.

Explicit CUG Invocation: Explicit CUG invocation is where a calling user attempts to invoke a CUG by passing CUG information to the network in a call request.

Implicit CUG Invocation: Implicit CUG invocation is where the user invokes some default characteristic of a CUG without providing any CUG information in the call request.

Normal Call: A normal call in the context of this CUG TS is a call established from a CUG subscriber where no CUG information is passed from the originating switching entity to the destination entity.

Outgoing Access Indicator: An indication passed from the point of origin to the destination in a CUG call to indicate that the calling user has subscribed to the Outgoing Access inter-CUG accessibility subscription option.

0.3 Abbreviations

In addition to those listed below abbreviations used in the present document are listed in GSM 01.04.

For the purpose of the present document the following abbreviations are apply:

BS Basic Service

CI CUG Index

CUG Closed User Group

IA Incoming Access

IC Interlock Code

IC(pref) Interlock code of the preferential CUG

IC+OA Interlock Code and Outgoing Access indicator.

ICB Incoming Calls Barred within the CUG

OA Outgoing Access

OCB Outgoing Calls Barred within the CUG

Pref CUG Preferential CUG

SOA Suppress OA

SPC Suppress Preferential CUG