URN Mapping

Every PubID can be mapped to a canonical URN (Uniform Resource Name) for machine interchange. URNs provide a stable, location-independent identifier.

What is a URN?

A URN is a standardized identifier syntax defined by RFC 8141. URNs follow the pattern:

urn:[namespace]:[specific-string]

PubID URN Patterns

Each publisher maps their PubID syntax to a URN following their specific pattern:

ISO

urn:iso:std:iso[:copublisher]:[number]:[edition]:[language]

PubID	URN
ISO 9001:2015	urn:iso:std:iso:9001:ed-5:en
ISO/IEC 17031-1:2020	urn:iso:std:iso-iec:17031:-1:ed-1
ISO 9001:2015/Amd 1:2024	urn:iso:std:iso:9001:ed-5:amd:1:v1

IEC

urn:iec:std:iec[:copublisher]:[number]:[edition]:[language]

PubID	URN
IEC 61131-3:2013	urn:iec:std:iec:61131:-3:ed-3
IEC 60050-111/AMD1/FRAG1 ED2	urn:iec:std:iec:60050:111:ed-2:amd:1:frag:1

IEEE

urn:ieee:std:[number]:[year]

NIST

urn:nist:pub:[type]:[number]:[revision]

PubID	URN
NIST SP 800-53 Rev. 5	urn:nist:pub:sp:800-53:r5
NIST SP 800-57 Part 1 Rev. 4	urn:nist:pub:sp:800-57:pt1:r4

NIST also defines a machine-readable (MR) style used as the DOI suffix: NIST.SP.800-53A maps to https://doi.org/10.6028/NIST.SP.800-53A.

OIML

urn:oiml:pub:[type]:[number]:[year]

Round-Trip Guarantee

PubIDs are designed for round-trip fidelity: parse a string, serialize it back, and get identical output. This applies to both human-readable PubID strings and URN representations.

Input:  "ISO 9001:2015"
  ↓ Parse
Object: { publisher: "ISO", number: "9001", year: 2015, edition: 5 }
  ↓ Render (PubID)
Output: "ISO 9001:2015"  ✓ identical
  ↓ Render (URN)
URN:    "urn:iso:std:iso:9001:ed-5:en"

This same principle applies across all output formats. For NIST, a single identifier can round-trip through four distinct styles:

Input:  "NIST SP 800-53A"
  ↓ Parse
Object: { publisher: "NIST", type: "SP", number: "800-53A" }
  ↓ Render (Short)
Output: "NIST SP 800-53A"  ✓
  ↓ Render (Full)
Output: "National Institute of Standards and Technology Special Publication 800-53A"
  ↓ Render (MR/DOI)
Output: "NIST.SP.800-53A"
  ↓ Render (URN)
URN:    "urn:nist:pub:sp:800-53a"

Benefits of URN Mapping

1. Machine interchange — Systems can exchange identifiers in a standardized format
2. Resolution — URNs can be used for identifier resolution services
3. Uniqueness — URNs provide globally unique identifiers
4. Stability — URNs are location-independent and persist over time

Implementation

The PubID Ruby library generates URNs through the to_urn method:

require 'pubid'

id = Pubid::Iso.parse("ISO 9001:2015")
id.to_urn  # => "urn:iso:std:iso:9001:ed-5:en"

id = Pubid::Iec.parse("IEC 61131-3:2013")
id.to_urn  # => "urn:iec:std:iec:61131:-3:ed-3"

See Also

• URN Specifications — Full ABNF grammar and reference documentation for ISO (RFC 5141-bis) and IEC URN namespaces
• The Metaschema
• Common Elements
• Library Quick Start