On 07/02/2019 22:20, Dilyan Palauzov wrote:
Strictly speaking the delivery for all recipients does not have to be delayed.
The server can deliver promptly the messages to all deserving recipients,
memorize the Message-Id and the per recipient response, and in subsequent
transactions communicate the status per recipient.
So, you're suggesting delivering the message to the recipient, even
though you've said it's been rejected?
That's not standards compliant... You don't KNOW that the sender is
going to retry it, and if it does, you don't know if it'll use the same
Message-Id, so the recipient may receive a message that the sender
thinks they didn't, or they may receive multiple duplicates, or
something else. You can't deliver it until/unless you say you'll deliver it.
The problems with the idea of 4xx rejecting recipients with different
rules are that you really don't know what the sender is going to do, you
are essentially removing the ability to send mail to multiple recipients
at once, and you are adding load everywhere - a message sent to 100
people at the same domain potentially has to be sent 100 times rather
than just once (even if all recipients will accept it), and there have
to be 5050 recipient checks rather than just 100, etc.
Is it that big a deal? If the recipient doesn't want the message, just
accept it and quarantine it... That'll may even cut down on support
calls - when a message is sent 'To: bob(_at_)example(_dot_)com, kate(_at_)example(_dot_)com',
and Kate receives the message, but Bob, who is sitting next to her,
doesn't and has no idea why because you PRDR rejected it because of a
rule that Bob turned on and didn't understand. (Or doesn't receive it
until a few hours later (if at all, if the sender times-out), because he
HASN'T got a *relevant* rule enabled, but does have some irrelevant
slightly different setting from Kate).
Paul Smith Computer Services
Tel: 01484 855800
Vat No: GB 685 6987 53
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