Canonical XML was created to provide a method for differentiating between XML documents that have the same logical structure, but might differ in content. The two Recommendations related to Canonical XML can be found at
Canonical 1.0
Exclusive XML Canonicalization Version 1.0
The first of these Recommendations deals with straightforward Canonical XML, whereas the Exclusive XML Canonicalization Recommendation deals with documents that have special needs, such as those with XML Signatures.
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