1

Scope and Field of Application

This International Standard specifies

(a) procedures for a single protocol for the transfer of data and control information from one session entity to a peer session entity;

(b) the means of selecting the functional units to be used by the session entities;

(c) the structure and encoding of the session protocol data units used for the transfer of data and control information.

The procedures are defined in terms of

(a) the interactions between peer session entities through the exchange of session protocol data units;

(b) the interactions between a session entity and the session service user in the same system through the exchange of session service primitives;

(c) the interactions between a session entity and the transport service provider through the exchange of transport service primitives.

These procedures are applicable to instances of communication between systems which support the Session Layer of the OSI Reference Model and which wish to interconnect in an open systems environment.

This International Standard also specifies conformance requirements fo r systems implementing these procedures. It does not contain tests which can be used to demonstrate this conformance.