Overview
ISO/IEC 10026-4:1995 - Information technology - Open Systems Interconnection (OSI) - Distributed Transaction Processing: Protocol Implementation Conformance Statement (PICS) proforma - defines the standard PICS template for implementations of the OSI Distributed Transaction Processing (TP) protocol. The document provides a prescriptive proforma (Annex A) and guidance for completing it so implementors can declare which protocol capabilities, options and limits their product supports. Annex B supplies implementation capability detail for reference.
Key topics and requirements
- PICS proforma structure: The proforma is divided into Identification, Conformance Claim, Support of Functional Units/Limits/Mechanisms, Support of TP APDUs, and Multi‑layer dependencies (Annex A).
- Mandatory content: A conforming PICS must uniquely identify the supplier and the implementation and preserve the published numbering/ordering of the proforma items.
- Functional units covered: Dialogue, shared control, polarized control, handshake, commit, recovery - implementors must state which functional units and roles are supported.
- TP APDU support: The proforma requires explicit statements of which APDUs, APDU fields and parameter values are implemented, and references to supporting detail where necessary.
- Limits and capabilities: Practical limits (e.g., concurrent dialogues, transaction branches, APDU size) should be declared - Annex B may be used to present such limits.
- Multi‑layer dependencies: Identification of required or implied OSI layer standards (session, presentation, etc.) and any dependencies on other protocols or profiles.
- Conformance testing guidance: The proforma aligns with conformance testing methodology in ITU‑T Rec. X.291 / ISO/IEC 9646‑2 and references the TP protocol specification in ITU‑T Rec. X.862 / ISO/IEC 10026‑3.
- Completion rules: Implementors must complete the proforma per the instructions given in the standard (clauses referenced in the proforma).
Applications and who uses this standard
- Software/hardware vendors producing OSI TP (Distributed Transaction Processing) implementations - to document supported features and claim conformance.
- Test laboratories and certification bodies - to evaluate, test and certify protocol conformance using a standardized PICS.
- Procurement and QA teams - to compare implementations objectively during acquisition and interoperability testing.
- System integrators and operators - to verify multi‑layer dependencies and limits for deployment planning in distributed transaction environments.
Related standards (for context)
Keywords: ISO/IEC 10026-4:1995, PICS proforma, Distributed Transaction Processing, OSI TP, protocol conformance, ITU‑T X.862, conformance testing, TP APDU.