CAN/CSA-ISO/IEC 13869-97 (R2001)

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.