ISO IEC 13865:2003 pdf download – Information technology — Telecommunications and information exchange between systems — Private Integrated Services Network — Specification, functional model and information flows — Call Transfer supplementary service. 1 Scope This International Standard specifies Supplementary Service Call Transfer (SS-CT), which is applicable to various basic services supported by Private Integrated Services Networks (PISNs). Basic services are specified in ISO/IEC 11574. SS-CT is a supplementary service which enables a user to transform two of that user’s calls (of which one must be answered) into a new call between the other two users of the two calls. Supplementary...