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Re: getting 2822 protection as well as 2821 protection

2004-04-07 08:59:49
Meng Weng Wong wrote:

How does this sound?  This way we get to protect the 2822 From:, which
is something we all do want to do --- we just don't want to do it in a
way that breaks too much else.

I would suggest that maybe an explicit match is too strict. My explanation is long-winded, so please bear with me :)

I uses Challenge/Response with VERP and various extension addresses as follows:

- My envelope is a dated address which expires after 14 days (long enough for any bounce, too short to be harvested)

- My From address is plain so my recipients recognize it. Replying to this plain address will cause a challenge to be sent.

- My Reply-to address is also dated and expires after 14 days (long enough for most recipients to reply to me, but too short to be harvested)

When a challenge email is sent as a result of someone sending email to my plain address or an expired dated address, it has the following characteristics:

- My envelope is a special extension address - It will be stored in a folder in case there are legitimate bounces, but most of these are bounces due to non-existent spam emails, and largely ignored.

- My From address is plain so my recipients recognize it.

- My Reply-to address is a specially-tagged address which will release the original message from the pending queue.

In all of these circumstances, all these various messages are similar, in that they have the following format:

i.am [ -optional-extensions ] @ [ optionalhostname. ] jimramsay.com

I propose a way of matching the Envelope to the Headers "within reason": That is, if the domain is mostly the same, and the front-part is mostly the same, consider it "first-class". For example, I think this could be considered close enough to say that an email is "first-class":

Envelope: i(_dot_)am-bounce-return(_at_)watson(_dot_)jimramsay(_dot_)com
From: i(_dot_)am(_at_)jimramsay(_dot_)com
Reply-to: i(_dot_)am-other-mailbox(_at_)jimramsay(_dot_)com
Sender: lack(_at_)holmes(_dot_)jimramsay(_dot_)com

[Note, please don't reply with "Don't use C/R it's evil" - I know why some people don't like C/R and I know why some people like C/R. My intent was not to start a discussion on C/R, but to note that there are other legitimate reasons for having envelopes which do not _exactly_ match the From: or Reply-to:, that matching "within reason" may be better than exact matching.]

--
Jim Ramsay
"Me fail English?  That's unpossible!"