Comparison, Equivalence and Canonicalization of Internationalized Resource Identifiers

Internationalized Resource Identifiers (IRIs) are Unicode strings used to identify resources on the Internet. Applications that use IRIs often define a means of comparing IRIs to determine when two IRIs are equivalent for the purpose of that application. Some applications also define a method for canonicalizing an IRI -translating one IRI into another which is equivalent under the comparison method used. This document gives guidelines and best practices for defining and using IRI comparison and canonicalization methods. Comparison methods are used to determine equivalence. As URIs are a subset of IRIs, the guidelines apply to URI comparison as well.