CORRIGENDUM Integrated Services Digital Network (ISDN); Connected Line Identification Restriction (COLR) Supplementary Service Digital Subscriber Signalling System No. One (DSS1) Protocol Part 1: Protocol Specification
This first part of ETS 300 098 specifies stage three of the Connected Line Identification Restriction (COLR) supplementary service for the pan-European Integrated Services Digital Network (ISDN) as provided by European public telecommunications operators at the T reference point or coincident S and T reference point (as defined in CCITT Recommendation I.411 [1]) by means of the Digital Subscriber Signalling System No. one (DSS1). Stage three identifies the protocol procedures and switching functions needed to support a telecommunications service (see CCITT Recommendation I.130 [2]). In addition this standard specifies the protocol requirements at the T reference point where the service is provided to the user via a private ISDN. This standard does not specify the additional protocol requirements where the service is provided to the user via a telecommunications network that is not an ISDN. The COLR supplementary service enables the connected party to prevent presentation of its ISDN number to the calling party@ and is applicable to all circuit-switched telecommunications services. Further parts of this standard specify the method of testing required to identify conformance to this standard. This standard is applicable to equipment@ supporting the COLR supplementary service@ to be attached at either side of a T reference point or coincident S and T reference point when used as an access to the public ISDN.