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Scope

This Recommendation / International Standard is to be applied by reference from other specifications. This is done within such specifications by reference to the CCR services defined in ITU-T Rec. X.851 / ISO/IEC 9804. A reference to a CCR service invokes the procedures of this Recommendation / International Standard to cause external effects.

This Recommendation / International Standard applies whenever the use of CCR services does not encompass any communication activity which makes direct or indirect use of the session activity management services defined in CCITT Rec. X.215 / ISO 8326. It can be used inside a session activity, and on a session -connection where the session activity functional unit is not in use. It can also be applied when the S-ACTIVITY service is used through the mechanisms of Annex B.

This Recommendation / International Standard specifies the static and dynamic conformance requirements for systems implementing these procedures. It does not contain tests which can be used to demonstrate conformance.

This Recommendation / International Standard specifies the following protocol versions:

(a) Protocol Version 1 which does not make use of the Session Data Separation functional unit. (b) Protocol Version 2 which makes use of the Session Data Separation functional unit to protect data not belonging to the CCR atomic action.