Unisig – Uniform signature

Unisig is a uniform signature scheme for binary file formats and network protocols.

A signature (aka magic number) is a series of constant bytes at the beginning of data that identifies its format.

Discoverable

  • Tools can find the signature at a known location
  • Signatures are human-readable web links

Resilient

  • Clearly differentiates binary data from text
  • Detects typical file transfer errors

Decentralized

  • URI as an extensible naming scheme
  • DNS avoids a separate central registry
  • Timestamps avoid domain ownership disputes
  • UUID as a stealthy alternative to URI

Standards-based

  • ASCII, Unicode
  • UUID
  • URI, URL
  • DNS, HTTP, HTML
  • ISO 8601, RFC 3339

Simple

  • Either 24 or 8+n constant bytes
  • Input: read() and memcmp()
  • Output: write()

Supported

  • Detected by the Unix file(1) utility
  • Detected by the TrID utility
  • Detected by the DROID utility
  • On record at the UK National Archives (PRONOM)

Resources

Make your own

Generate a signature for your new file format or network protocol.