Subject: Re: Last Call: Anti-Spam Requirements on an SMTP MTA to BCP

From: "Marcus Leech" <[email-masked]>
Date: Wed, 04 Mar 1998 11:38:31 -0500

Perry E. Metzger wrote:
> 
> Jacob Palme writes:
> > We started implementing anti-spam features which check the
> > correctness of the domains of senders of incoming messages a few
> > weeks ago. This did reduce the amount of spamming temporarily, but it
> > is growing again, obviously the spammers have found ways to work
> > around such measures.
> 
> True enough, but this has a very salutory effect.
> 
> It means that anyone spamming now has to steal someone's domain name
> -- that is, to commit a kind of fraud. That generally means there is
> someone who can sue them for damages, which is happening more and more
> often (and which usually succeeds).
We're starting to implement inbound spam filtering based on content
  "signature", rather than just headers.  Even filtering on headers
  will reduce our inbound spam by about 70%.  Each of the spam
  packages has a distinct "fingerprint". The fingerprints corresponding
  to the "STEALTH" e-mail spam software constitute about 50% or more of
  our inbound spam.

-- 
----------------------------------------------------------------------
Marcus Leech                             Mail:   Dept 8M86, MS 012, FITZ
Systems Security Architect               Phone: (ESN) 393-9145  +1 613
763 9145
Messaging and Security Infrastructure    Fax:   (ESN) 395-1407  +1 613
765 1407
Nortel Technology              [email-masked]
-----------------Expressed opinions are my own, not my employer's------