Specification of GMS Access Protocol (GAP) Version 1.0

Group communications require special support for name and address management, QoS support, and connection establishment. The group and session management system (GMS) is a distributed directory system which is specifically designed to support group communication infrastructures. This report briefly introduces the concepts of GMS, the data types available, and then gives a specification of GAP, the GMS access protocol. GAP is specified by state diagrams describing the behavior of two communication entities, the PDU syntax in ASN.1, and the PDU semantics in comments given for each PDU.