On Thu May 19 08:27:05 2011, Jacek Konieczny wrote:
On Wed, May 18, 2011 at 10:12:21AM -0600, Peter Saint-Andre wrote:
> <dialback xmlns='urn:xmpp:features:dialback'/>
> <dialback xmlns='urn:xmpp:features:dialback:errors'/>
> <dialback xmlns='urn:xmpp:features:dialback:muliplexing'/>
> <dialback xmlns='urn:xmpp:features:dialback:piggybacking'/>
Why four different namespaces for one protocol? Why not four
different
elements in a single namespace? Or an element with subelements
(options)?
I entirely disagree with the argument that follows, but for the
record:
The argument is that because different options are introduced at
different times, and being options may not be implemented, then this
results in a volatile schema with respect to time.
That is, at different times, and in effect on different
implementations, the schema may have different elements potentially
available.
Now, I disagree that this is an issue to be concerned about, because
the elements present in the schema of whatever time and place all
have exactly the same semantics. No matter the sender's idea of the
schema, elements are either unknown or have a defined and well-known
semantic associated with them. We do not do schema validation in
XMPP, for good reason, so this will not have any effect on
interoperability.
Dave.
--
Dave Cridland - mailto:[email protected] - xmpp:[email protected]
- acap://acap.dave.cridland.net/byowner/user/dwd/bookmarks/
- http://dave.cridland.net/
Infotrope Polymer - ACAP, IMAP, ESMTP, and Lemonade