ietf-mxcomp
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Re: Input on identities

2004-04-08 11:19:48

On Thu, Apr 08, 2004 at 01:45:34PM -0400, Alan DeKok wrote:
  So you're not supposed to validate the EHLO field.

And the standard answer to this is:

    7.7 Scope of Operation of SMTP Servers
       It is a well-established principle that an SMTP server may refuse to
       accept mail for any operational or technical reason that makes sense
       to the site providing the server.

We e.g. have enough operational and technical reason to not accept
messages from hosts using HELO arguments

    mail.space.net
    195.30.0.8
    YOUR.HOST.NAME
    apple.com
    compuserve.com
    coolmail.com
    cyberproxy.com
    domainnames.r-us.com.au
    earthling.net
    earthlink.net
    excite.com
    localhost.localdomain
    mail.com
    usagreetings.com
    [ ... ]

and it would also be in full conformance with the RFC if for operational
reasons we would choose to not accept messages from hosts that use HELO
arguments that do not resolve.
On some mailservers we do, on some other mailservers it would cause too
much harm for the eMail communication of the customer.
(see my other post with some numbers).

        \Maex

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