ISO/IEC 9804:1998

Overview

ISO/IEC 9804:1998 - Information technology - Open Systems Interconnection - Service definition for the Commitment, Concurrency and Recovery (CCR) service element - defines the CCR application-service-element for coordinating atomic actions in distributed applications. Published as an ITU‑T Recommendation (X.851), this standard specifies service semantics used on a single association to organize two (and, by referenced coordination, more) application‑entity invocations into an atomic action and to support recovery after failure. It is a service definition, not an implementation specification, and requires CCR Protocol Version 2 (or later) when used.

Key topics and requirements

• Purpose: provide services for commitment, concurrency control and recovery on a single OSI association to support atomic actions in distributed systems.
• Scope constraints:
  • The standard does not determine which application‑entity invocations participate in an atomic action.
  • It does not mandate implementations or constrain internal entity interfaces.
  • Compliance requirements apply to referencing specifications that adopt CCR.
• Defined service primitives (selection from clause 7):
  • C-INITIALIZE, C-BEGIN, C-PREPARE, C-READY, C-COMMIT, C-ROLLBACK
  • C-NOCHANGE, C-CANCEL, C-RECOVER, C-P-ERROR
• Coordination model:
  • Establishes general principles for coordinating CCR when more than two invocations are involved or recovery after failure is needed.
  • Coordination across multiple associations is achieved by combining this standard with a referencing specification.
• Supporting material:
  • Annex A: CCR service‑user rules (mandatory guidance for referencing specs)
  • Annex B: relationship to Application Layer Structure
  • Annex C: tutorial and implementation guidance (informative)

Applications and who would use it

• Standards authors and protocol designers creating distributed transaction or atomic action specifications that reference OSI Application Layer services.
• Middleware and transaction manager architects who need a formal CCR service model for commit/rollback, concurrency control and failure recovery semantics.
• Vendors implementing OSI‑based application layer services or middleware that must interoperate with CCR‑aware applications.
• System designers of distributed applications that require atomicity, coordinated two‑phase operations, or recovery support across networked components.

Related standards

• ISO/IEC 7498-1 (OSI Basic Reference Model) - conceptual basis
• ISO/IEC 8822 (Presentation service definition)
• ISO/IEC 9545 (Application Layer Structure)
• ISO/IEC 9805-1 / ITU‑T X.852 (CCR protocol specification)
• ISO/IEC 8650-1 / ITU‑T X.227 (Association Control service definition)
• ITU‑T X.851 is the equivalent Recommendation.

Keywords: ISO/IEC 9804:1998, CCR, Commitment Concurrency Recovery, Open Systems Interconnection, atomic action, distributed application, CCR Protocol Version 2, service definition.