Hi,
From: "Peter van Dijk" <[EMAIL PROTECTED]>
> > advertise the e-mail address associated with that user account in the
MAIL
> > FROM, nothing prevents you to advertise your "official" email address in
the
> > reply-to header.
>
> Uhm. You are correct. Nothing prevents you from doing that. But it kinda
> defeats the purpose of being able to dialin anywhere in the world, POP
mail
> off your home-provider and send thru the relay of the ISP you're dialing
> into.
Well I think that the better answer in this case would be to use your
home-provider's SMTP relay using either SMTP-after-POP or SMTP AUTH or TLS
or whatever other scheme that will let you use your *normal* relay.
Since you are already accessing you home provider's services (the POP
account), you should be able to also its mail relay.
Again I am not saying that this is practical today. My only claim is that
you should be able to use the domain indicated in MAIL FROM to do validity
checks and possibly reject spam.
> > This amounts to enforcing stricter relay servers: should a server relay
mail
> > if the address presented in MAIL FROM does not belong to one of its
domains
> > (in addition to does it come from one of the "local" computers, etc.) ?
>
> Yes it should. Relaying should be based on IP, either fixed (subnets) or
> dynamic (SMTP-after-POP), and _nothing_ else.
>
I think that this is debatable (cf. my comment above).
If I am an ISP, why should I let somebody use my mail servers to relay
messages that pretend they are not from one of my users (including any
virtual domains that I may have) ?
> Anyway, most people here will agree that the rules you are proposing are
> insane, because you will prevent your customers from using a POP-account
at
> another ISP.
When you configure a POP account in your MUA, you usually configure a SMTP
server along with it. Why not configure that ISP's SMTP server ?
Please note that I am not trying to start a flame war. I just want to have
strong arguments as to why that method should or should not be used. So far
we have:
- travelling users may be impacted badly by this, unless they always use
their "home" mail relay (how feasible is it today ? should it be enforced
?).
- this could work with yahoo or hotmail (because the only way you can use
their relays is via their web interface)
- this is insane (this is the point I have trouble with :)
Patrick.
