Yes, some kind of canonicalization sounds like what you want.
If you have qnames in content (E.g., like xslt), then you need exc-c14n.
Do you have to care about namespace declarations moving?
<foo xmlns:tns="....">
<tns:xxx>...
compared to
<foo>
<tns:xxx xmlns:tns="....">...
If not, then a simple expat-based processor that sorted attributes
and always wrote closing tags will probably work fine.
/r$
--
Rich Salz Chief Security Architect
DataPower Technology http://www.datapower.com
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