commitment, concurrency and recovery is required. It can be referenced whenever the processing of two or more

application-entity invocations in a distributed application needs to be organized into an atomic action.

This Recommendation | International Standard defines services that are used on a single association to coordinate two

application-entity invocations involved in an atomic action. The determination of which application-entity invocations

are involved in an atomic action is not within the scope of this Recommendation | International Standard.

This Recommendation | International Standard establishes the general principles for the coordinated use of the CCR

services when more than two application-entity invocations are involved in a single atomic action, or when recovery is

required after failure. The coordination of multiple associations and the related application-entity invocations that

constitute an atomic action is achieved by a referencing specification in conjunction with this Recommendation |

International Standard.

This Recommendation | International Standard is only applicable to a distributed application whose specification

references this Recommendation | International Standard.

This Recommendation | International Standard does not specify individual implementations or products. It does not

constrain the implementation of entities and interfaces within a computer system.

No requirement is made for conformance to this Recommendation | International Standard.

This Recommendation | International Standard includes requirements for compliance that apply to a referencing

specification.

The CCR service defined in this Recommendation | International Standard requires that CCR Protocol Version 2 (or a

later version) is being used.

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 specifies, in clause 9, a use of the ACSE, Presentation and Session

services to carry the CCR semantics. This "reference" mapping can be used whenever the use of these services does not

conflict with the user made by other ASEs or ASOs that are using the same association. Annex B defines how a different

use of supporting services may be specified, for use where the reference mapping is inappropriate.

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 edition of this Recommendation | International Standard specifies CCR protocol Version 2, which makes use of the

Session Data Separation functional unit to protect data not belonging to the CCR atomic action. The 1990 edition of

ISO/IEC 9805 specified CCR protocol Version 1. The 1993/1994 edition of this Recommendation | International

Standard specified both CCR protocol Version 1 and CCR protocol Version 2, for the static commitment functional unit

only.

This International Standard specifies the protocol elements that support the following functional units:

a) static commitment;

b) dynamic commitment;

c) read only;

d) one-phase commitment;

e) cancel; and

f) overlapped recovery.

This Recommendation | International Standard specifies:

? procedures for the transmission of management information between application entities;

? the abstract syntax of the Common Management Information Protocol (CMIP) and the associated encoding rules to be applied;

? procedures for the correct interpretation of protocol control information;

? the conformance requirements to be met by implementation of this Recommendation | International Standard.

This Recommendation | International Standard does not specify:

? the structure or meaning of the management information that is transmitted by means of CMIP;

? the manner in which management is accomplished as a result of CMIP exchanges;

? the interactions which result in the use of CMIP.

This Recommendation | International Standard defines:

? a set of service primitives that constitute the application service element;

? the parameters that are passed in each service primitive;

? any necessary information for the semantic description of each service primitive.

This Recommendation | International Standard does not define:

? the nature of any implementation intended to provide the defined service;

? the semantics associated with the information or commands that are exchanged by means of the service;

? the manner in which management is accomplished by the user of the service;

? the nature of any interactions which result in the use of the service.

No requirement is made for conformance to this Recommendation | International Standard.