Re: Sender-ID != SPF
Douglas Otis <[email protected]>
| Newsgroups | gmane.ietf.mxcomp |
|---|---|
| Message-ID | <[email protected]> |
On Sun, 2004-10-31 at 04:29, James Couzens wrote:
> On Fri, 2004-10-29 at 15:46 -0700, Douglas Otis wrote:
> > On Fri, 2004-10-29 at 09:44, James Couzens wrote:
> >
> > > SenderID != SPF. Please don't associate the two.
> >
> > I agree. How does one establish a mix of divergent approaches? A chain
> > of trust is broken when each node checks a different mailbox-domain. It
> > is also seems inappropriate to misapply a record intended for a
> > different mailbox-domain. Handing multiple accountable identities is
> > daunting, especially when a change in convention between administrative
> > domains makes spoofing easy. Correlating the mailbox-domain checked and
> > then displayed becomes another matter.
> >
> > Regardless of the mailbox-domain checked, leaving authorization normally
> > open-ended overcomes present problematic header conventions. Only
> > institutions dealing with a phishing problem would have an incentive to
> > tackle closing the authorization list. Changing from an address-list to
> > a name-list overcomes exploits invited by an open-ended authorization
> > list as well, as this would imply a separate entity is utilized for
> > reputation.
>
> . o O Mmmmmm... I wonder just how it was possible that something like
> the KISS principle was completely cast aside instead opting to do the
> exact opposite.
KISS Principles?
1) Email authentication must aid security and reputation assessment.
2) Only the administrator of each MTA is accountable for its security.
3) Only a validated HELO-domain directly identifies the administrator.
4) Lack of security is the principle enabler of spam.
5) Reputation remains a principle tool to abate spam.
6) Any mailbox-domain within a message is hearsay without a signature.
7) Reputation should be based upon the administrator's response to
notification of a security breach.
8) Reputations based upon a mailbox-domain with a prescribed
mail-channel invites litigation.
9) A prescribed closed-ended mail-channel breaks SMTP.
10) An open-ended prescribed mail-channel, when combined with
mailbox-domain reputation, invites spoofing.
11) An open-ended prescribed mail-channel, when reputation is based upon
the administrator, does not invite spoofing nor breaks SMTP.
12) Prescribing a mail-channel using a root-name-list of HELO domains
is achieved within a single lookup without the need for script.
13) Prescribing a mail-channel using a comprehensive address-list may
require many scripts and perhaps hundreds of lookups to resolve.
14) Any script, especially extensible scripts, pose risk.
15) Script within email imposes greater risk than that in a browser.
16) Script within email & DNS imposes greater risk than script in email.
-Doug