scope:

Scope and purpose

This standard is one of a series that defines and describes supplementary services within the context of an Integrated Services Digital Network (ISDN). The interaction of this service with other ISDN services is also included. The purpose of the standard is to allow maximum compatibility among network- and user- owned telecommunication equipment in order to increase the attractiveness and usefulness of ISDN-based capabilities.

Application

This service applies to both an ISDN basic rate access and ISDN primary rate access and is intended to supplement the basic circuit mode bearer services contained in American National Standard for Telecommunications - Integrated Services Digital Network (ISDN) - Circuit Mode Bearer Service Category Description, ANSI T1.620.¹⁾ It should be used in conjunction with other ISDN standards for ISDN supplementary services for a complete understanding of the interactions between this and other ISDN services.

This supplementary service is applicable to all circuit mode bearer services (see American National Standard for Telecommunications - lntegrated Services Digital Network (ISDN) - Circuit Mode Bearer Service Category Description, ANSI T1.620¹⁾).