Information technology - Telecommunicaitons and information exchange between systems - Private Integrated Services Network - Inter-exchange signalling protocol - Call diversion supplementary services
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 13873:1995. 1 Scope This International Standard specifies the signalling protocol for the support
of Call Diversion supplementary services (SS-DIV) at the Q reference point
between Private Integrated Services Network Exchanges (PINXs) connected
together within a Private Integrated Services Network (PISN). The Call
Diversion supplementary services are Call Forwarding Unconditional (SS-CFU),
Call Forwarding Busy (SS-CFB), Call Forwarding No Reply (SS-CFNR) and Call
Deflection (SS-CD). SS-CFU, SS-CFB, SS-CFNR and SS-CD are supplementary services which permit a
served user to have the PISN send all or specific incoming calls addressed to
the served user's PISN number to another number. 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 Rec. 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 13872. The signalling protocol for SS-DIV 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
SS-DIV and other supplementary services and ANFs. This International Standard is applicable to PINXs which can be interconnected
to form a PISN.