XML-Signature WG

Canonical XML-comments

Author(s):

Ed Simon, Entrust <ed.simon@entrust.com>

The XML Signature WG has reviewed the 19 January 2000 draft of Canonical XML. Though we have
some non-mandatory concerns about normalizing character encodings, we feel the draft meets our requirements for doing "XML aware canonicalization." (We will also specify a minimal canonicalization that treats the content as text only.)

For the record, this note includes a summary of our discussions regarding two topics related to Canonical XML. The first topic is the character encoding one just mentioned; the second deals with the treatment of serializing XPath returns.

Normalization of character encoding (section 5.1 of Canonical XML issued 19 Jan 2000):

The XML Signature WG sees no signature or security implications with respect to the normalization of character representation. However, as a community of XML application developers we are concerned that requiring implementors to do such normalization may be introducing more complexity than is reasonable for the stated benefit. No Working Group member has advocated the character normalization as specified and a few members have expressed concern about its requirements on limited processors.

Canonicalization of XML Fragments:

The XML Signature WG discussed whether our requirement to serialize and canonicalize the results of XPath expressions (particularly node-set results) should be met by Canonical XML. We determined that if even if the serialization and canonicalization of XPath results is an issue for the XML Signature WG, it needs to be resolved by the XML Signature WG and is not an issue for the Canonical XML WG.

In summary, we thank the Canonical XML WG for their efforts and look forward to further implementation experience and reports -- both from our own community and others.

Last revised by Reagle $Date: 2000/08/09 19:33:58 $