The Efficient XML Interchange Working Group has published a Working Draft of Canonical EXI. Any EXI document is part of a set of EXI documents that are logically equivalent within an application context, but which vary in physical representation based on differences permitted by the Efficient XML Interchange (EXI) Format 1.0 (Second Edition). This specification describes a relatively simple method for generating a physical representation, the canonical form, of an EXI document that accounts for the permissible changes. An example of the applications targeted by this specification is one that needs to guarantee non-repudiation using XML Signature yet allows certain flexibility for intermediaries to reconstitute the documents before they reach final destination without breaking the signatures. Note that two documents may have differing canonical forms yet still be equivalent in a given context based on more elaborate application-specific equivalence rules which is out of scope of this specification. Learn more about the Extensible Markup Language (XML) Activity.