Can XDSIG work with XML Schema applications?
Yes, with some caveats. XML Schema 1.0 does two things. First, it validates an instance according to a schema, this has no affect on XDSIG. Second, it also might modify the infoset resulting from parsing and validating the instance. For example, “Schemas may also provide for the specification of additional document information, such as normalization and defaulting of attribute and element values.” These changes are typically reflected in the “augmented infoset” as a “[schema normalized value]”. In a naive mapping to the XPath data model, these changes would not be retained. A more careful mapping or serialization/re-parsing is more likely to retain this information. Regardless, XDSIG’s Transform extensibility permits careful treatment of this issue as shown by the UDDI Schema Centric Canonicalization. However, for XDSIG to adopt and support schema augmented infosets as its native data model (and processing/transforms) it would have to be modified to rely upon schema aware XPath 2.0 and
