Filtering CDR open

[Eric Murray]

On Sat, Mar 03, 2001 at 01:15:25AM -0500, Declan McCullagh wrote:
> FYI I'm subscribed to cypherpunks from one address; I post to it 
> from a second; my From: line is a third. I sometimes use a fourth address
> to post.

You're not the only one who does that.

> I'm not sure how you're going to handle that, but you might want to consider
> semi-automated ways of extracting addresses from "known good" posts,
> to the extent that any of mine fit that category.

Since the goal is to block spam, not to prevent all non-subscribed
posters from posting, I put that in place before I announced the list.


Bounces (from not being on the posters list) go to me.   If it looks
like it's not spam, I have a script which strips off the outer envelope
and forwards the mail to the list, adding the contents of the From:
line to a list of addresses that's sorted into the major posters list.

So far I've added 39 addresses that way, 5 of which appear to be remailers.
Of the rest, roughly half are people who're cross-posting from other lists
like coderpunks or cryptography (or both), and the rest are
people who're posting from alternate addresses. 

There's 2-3 spam emails for every list email.   Previously I'd been
filtering most of the spam.  I had no idea it'd gotten this bad.


-- 
  Eric Murray           Consulting Security Architect         SecureDesign LLC
  http://www.securedesignllc.com                            PGP keyid:E03F65E5