[sipcore] Extensions to the reg event package

"Worley, Dale R (Dale)" <dworley@avaya.com> Thu, 21 October 2010 17:45 UTC

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From: "Worley, Dale R (Dale)" <dworley@avaya.com>
To: "sipcore@ietf.org" <sipcore@ietf.org>
Date: Thu, 21 Oct 2010 13:44:25 -0400
Thread-Topic: Extensions to the reg event package
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Subject: [sipcore] Extensions to the reg event package
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I've noticed that extensions to the reg event package are done by introducing new namespaces.  Since extensions usually add only one or two data items to the package, the result can be an XML document with many namespaces,  most of which have a very few element types being used.  It seems to me to be more natural for extensions to add elements to the original XML schema.  And since the interpreter of the XML document will ignore any elements that it does not recognize, this practice would be upward-compatible.  I suspect that there is some formal reason why extending an existing namespace is not done.