Overview
ISO/IEC 23681:2019 - Self-contained Information Retention Format (SIRF) Specification - defines a vendor-neutral, archival-style container model for long-term digital preservation. The standard specifies SIRF Level 1 and its serialization for tape and cloud targets (LTFS, SNIA CDMI and OpenStack Swift). It provides a logical “container” concept with an embedded catalog that captures metadata about the container and each preservation object, enabling archivists and IT teams to manage, verify and retrieve preserved digital content over time.
Key technical topics and requirements
- Container model and catalog: SIRF defines a self-contained storage container that includes a machine-readable catalog describing the container and member objects.
- Metadata categories: The standard details container information metadata (e.g., Specification Category, Container ID, State, Provenance, Audit Log) and object information metadata (e.g., Object IDs, Dates, Related Objects, Packaging Format, Fixity, Retention, Audit Log, Extension).
- Fixity and provenance: Explicit support for integrity checks (fixity) and provenance/audit metadata to demonstrate authenticity and chain-of-custody.
- Serializations: Guidelines for serializing the SIRF catalog for LTFS, SNIA CDMI and OpenStack Swift object storage, including XML and JSON examples (Annexes provide schema and samples).
- Operational considerations: SIRF anticipates computational tasks (fixity verification, transformations) can be performed close to data (e.g., using storlets) to reduce bandwidth, improve security, and capture provenance.
- Interoperability: Designed to be compatible with archival practice and existing preservation metadata approaches (references include PREMIS, JSON, CDMI, LTFS, OpenStack Swift).
Practical applications and who uses it
SIRF is targeted at organizations that require durable, auditable preservation of fixed digital content:
- Archivists and records managers seeking a digital analogue of archival containers (boxes/folders) to aggregate and describe related items.
- Libraries, national archives and museums implementing large-scale digital preservation programs.
- Enterprises and regulated industries (legal, healthcare, finance) needing retention, compliance, and defensible audit trails.
- Storage architects and cloud/tape vendors implementing LTFS, CDMI, or OpenStack Swift support for preserved repositories.
- Developers of preservation workflows who need a standardized catalog, fixity strategies, and serialization formats (XML/JSON).
Related standards and resources
- ISO/IEC 17826:2012 - Cloud Data Management Interface (CDMI)
- ISO/IEC 20919:2016 - Linear Tape File System (LTFS)
- PREMIS (preservation metadata recommendations)
- OpenStack Swift, JSON (ECMA-404)
- OpenSIRF open source implementations and examples
ISO/IEC 23681:2019 helps bridge archival practice and modern storage systems by defining a practical, interoperable format for long-term digital retention, with emphasis on metadata, integrity and portability.