http://www.rfc-editor.org/rfc/rfc2276.txt
RFC 2276: Architectural Principles of Uniform Resource Name Resolution, K. Sollins1998-01-01T23:00:00-00:00This document addresses the issues of the discovery of URN (Uniform Resource Name) resolver services that in turn will directly translate URNs into URLs (Uniform Resource Locators) and URCs (Uniform Resource Characteristics). This memo provides information for the Internet community. It does not specify an Internet standard of any kind.