Re: Serving agents and duplicates (was: Protocol changes in draft-allbery-usefor-usepro-00)

["Charles Lindsey" <[e-mail]>]

In <[e-mail]> Russ Allbery <[e-mail]> writes:

>Charles Lindsey <[e-mail]> writes:

>I now have:

(Presumably in section 3.6)

>   3.  It MUST reject any article that has already been successfully
>       sent to it, based on the Message-ID header field of the article.
>       To satisfy this requirement, a relaying agent normally keeps a
>       database of message identifiers it has already accepted.

>   4.  It SHOULD reject any article that matches an already-received and
>       honored cancel message or Supersedes header field following the
>       same rules as a relaying agent (Section 3.5).

OK. That is better. Though in fact it might wait until it sees the actual
article before deciding whether to honor the cancel.

>which is basically the same text as for relaying agents.

>> OK, but people will think it odd that you mention the obscure case of
>> cancels which arise first here, but make to mention of the common case.
>> Perhaps an extra step to say that it SHOULD then process any control
>> messages (including cancels) in acccordance with section 5.

>This would need to be added to relaying agents as well.

ITYM serving agents. Relaying agents should always just pass the cancel
message on and let serving agents downstream decide for themselves whether
to honour it.

But for serving agents, in addition to the wording above, you need at the
least a NOTE or a remark in parentheses to the effect that

"Cancel messages and Supersedes header fields arriving later then the
affected article are to be processed as described in section 5.3."

-- 
Charles H. Lindsey ---------At Home, doing my own thing------------------------
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