1. A means based upon the OSI–Reference Model to support applications in telecommunications networks. 2. Protocol functions and procedures that control non-circuit related information exchange among signaling points in SS7 networks. It provides a general purpose approach to the introduction of new services within a network as well as a framework for service architecture for providing internetwork services. Transaction capabilities includes the application layer protocol called transaction capabilities application part (TCAP) as well as the supporting Presentation, Session, and Transport layers called the application service part (ASP. )