Overview
ISO 8571-4:1988/Amd 4:1992 is Amendment 4 to Part 4 of the ISO 8571 series - the File Protocol Specification for FTAM (File Transfer, Access and Management) within the OSI (Open Systems Interconnection) framework. Published in 1992, this amendment updates the original 1988 specification by modifying protocol behavior text, refining parameter naming and ASN.1 notes, and replacing Annex A (protocol state tables). It clarifies presentation context handling, recovery/restart behavior and adds a formal Rules of extensibility for the F-INITIALIZE request.
Key topics and requirements
- Protocol text corrections and clause changes
- Removal of subclause 6.2.4 and several targeted edits to clauses 7, 8, 9, 10, 11–19 to clarify behavior and state transitions.
- Presentation context management
- New and revised subclauses (notably 8.3.1, 8.3.2 and multiple edits in 8.9.x and 8.13.x) change how PDUs are preserved or confirmed depending on the presentation action parameter and availability of the presentation context management functional unit.
- Error recovery and restart semantics
- Clarifications to FERPM (file error recovery protocol machine) and F-RESTART/F-RECOVER behaviors, including who sends recovery-point parameters and how restart checkpoints are handled.
- ASN.1 and parameter rules
- Added ASN.1 notes (subclause 20.3) and new subclause 20.5 Rules of extensibility: responders must ignore undefined elements in F-INITIALIZE and treat unnamed named-bits as insignificant.
- Protocol state tables
- Annex A (Protocol state tables) replaced - providing updated state-machine descriptions (FPM, FERPM, regime and bulk transfer machines), naming conventions and local signal definitions.
- Terminology and naming corrections
- Many editorial corrections (e.g., Presentation/Session capitalization, synchronization point naming, PSDU vs PDU) to ensure consistent implementation.
Applications and who uses it
- Implementers of FTAM protocol stacks and OSI-based file transfer solutions
- Vendors building or maintaining file-transfer components in OSI environments
- Systems integrators and protocol engineers working on interoperability and conformance testing
- Test labs and QA teams validating behavior for recovery, presentation negotiation and state-machine conformance
- Architects referencing OSI-based file protocol semantics or migrating legacy FTAM systems
Related standards
- ISO 8571 series (Parts 1–5): general introduction, virtual filestore, file service definition, file protocol specification, and conformance statement proforma
- ISO/IEC JTC 1 publications relevant to OSI and information technology standards
Keywords: ISO 8571-4, FTAM, file protocol, Open Systems Interconnection, file transfer access and management, protocol state tables, ASN.1, error recovery, presentation context, ISO amendment.
Open preview (PDF)Information processing systems — Open Systems Interconnection — File Transfer, Access and Management — Part 4: File Protocol Specification — Amendment 4
