Skip to main content

4.3. URNs and Relative References

Section 5.2 of [RFC3986] describes an algorithm for converting a URI reference that might be relative to a given base URI into "parsed components" of the target of that reference, which can then be recomposed per RFC 3986, Section 5.3 into a target URI. This algorithm is problematic for URNs because their syntax does not support the necessary path components.

However, if the algorithm is applied independent of a particular scheme, it should work predictably for URNs as well, with the following understandings:

  1. A system that encounters a <URI-reference> that obeys the syntax for <relative-ref>, whether it explicitly has the scheme "urn" or not, will convert it into a target URI as specified in RFC 3986.

  2. Because of the persistence and stability expectations of URNs, authors of documents that utilize URNs should generally avoid the use of the "urn" scheme in any <URI-reference> that is not strictly a <URI> as specified in RFC 3986.

Last updated on