Re: [apps-discuss] Feedback on draft-moonesamy-smtp-ipv6-00

Tony Finch <dot@dotat.at> Tue, 15 November 2011 11:12 UTC

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Date: Tue, 15 Nov 2011 11:12:11 +0000
From: Tony Finch <dot@dotat.at>
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Subject: Re: [apps-discuss] Feedback on draft-moonesamy-smtp-ipv6-00
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John R. Levine <johnl@iecc.com> wrote:
>
> Ah, right.  Can you suggest language that means "if you get a 4yz do whatever
> you do now."

It's already specified in RFC 5321:

   Although the capability to try multiple alternative addresses is
   required, specific installations may want to limit or disable the use
   of alternative addresses.  The question of whether a sender should
   attempt retries using the different addresses of a multihomed host
   has been controversial.  The main argument for using the multiple
   addresses is that it maximizes the probability of timely delivery,
   and indeed sometimes the probability of any delivery; the counter-
   argument is that it may result in unnecessary resource use.  Note
   that resource use is also strongly determined by the sending strategy
   discussed in Section 4.5.4.1.

I'm not sure what SM's draft is for, since RFC 3974 is obsoleted by RFC 5321
(even though the RFC index fails to say so).

Tony.
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