framework
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This memo defines a framework for extending the SMTP service by
defining a means whereby a server SMTP ...
... SMTP service
are registered with the IANA. This framework does not require
modification of existing SMTP clients ...
... haphazard entities, this document enhances SMTP in a straightforward
fashion that provides a framework in which all future extensions can
be built in a single consistent way.
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... Framework for SMTP Extensions ...
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Given this environment, the framework for the extensions described in
this memo consists of:
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... All esmtp-keyword values must be registered as part of the IANA
registration process described above. This definition only provides
the framework for future extension; no extended MAIL FROM or RCPT TO
parameters are defined by this RFC.
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