requirement
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The profiling requirements of [SASL] require that the following
information be supplied by a protocol definition:
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... XML stanzas between any two entities.
Beyond the requirement for in-order processing, each server
implementation will contain its own "delivery tree ...
... XMPP does not require the parsing of arbitrary and
complete XML documents, there is no requirement that XMPP needs to
support the full feature set ...
... Core Compliance Requirements ...
... instant messaging and presence applications built
on top of the core protocols). Compliance requirements that apply to
all servers and clients are specified in this section; compliance
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... all servers and clients are specified in this section; compliance
requirements for instant messaging servers and clients are specified
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... Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. ...
... Day, M., Aggarwal, S., Mohr, G., and J. Vincent, "Instant Messaging / Presence Protocol Requirements", RFC 2779, February 2000. ...