Information technology - Telecommunications and information exchange between systems - Private Integrated Services Network - Inter-exchange signalling protocol - Call transfer supplementary service
The international community has decided to make this standard available only in
the English language version. It has been adopted as a National Standard of
Canada on this basis. This National Standard of Canada is equivalent to International Standard
ISO/IEC 13869:1995. 1 Scope This International Standard specifies the signalling protocol for the support
of the Call Transfer supplementary service (SS-CT) at the Q reference point
between Private Integrated Network Services Exchanges (PINXs) connected
together within a Private Integrated Services Network (PISN). SS-CT is a supplementary service which enables a User to transform two of that
User's calls (at least one of which must be answered) into a new call between
the two other users in the two calls. The Q reference point is defined in ISO/IEC 11579-1. Service specifications are produced in three stages and according to the method
specified in CCITT Recommendation I.130. This International Standard contains
the stage 3 specification for the Q reference point and satisfies the
requirements identified by the stage 1 and stage 2 specifications in ISO/IEc
13865. The signalling protocol for SS-CT operates on top of the signalling protocol
for basic circuit switched call control, as specified in ISO/IEC 11572, and
uses certain aspects of the generic procedures for the control of supplementary
services specified in ISO/IEC 11582. This International Standard also specifies additional signalling protocol
requirements for the support of interactions at the Q reference point between
Call Transfer and other supplementary services and ANFs. This International Standard is applicable to PINXs which can interconnect to
form a PISN.