Merit Network
Can't find what you're looking for? Search the Mail Archives.
  About Merit   Services   Network   Resources & Support   Network Research   News   Events   Home

Discussion Communities: Merit Network Email List Archives

North American Network Operators Group

Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical

Re: How do you stop outgoing spam?

  • From: Valdis.Kletnieks
  • Date: Tue Sep 10 12:43:19 2002

On Tue, 10 Sep 2002 09:12:15 PDT, Joe St Sauver said:
> Actually, our experience *does* follow the backoff paradigm: if you block a 
> particular source of spam, that rejection *does* seem to trigger "message
> volume" backoff at the source, with only periodic check probes apparently 
> designed to see if the spam source is really still blocked (and of course 
> it really still is). 

Yes - but since they need to have N replies to their spam to make it worth
the effort, they will just pound on somebody ELSE.  I saw one quote from
a very unapologetic spammer who was complaining that with all these blocks
he had to send a lot more spam and his costs were up 1000% as a result.

Let's say a spammer needs 100 replies to turn a profit, and 1% of the things
that make it into a mailbox get a reply.  If nobody blocks spam, then the
spammer only needs to send 10K messages before he profits.  If 99% of spam
is blocked, he has to send a million.  That's why we're seeing statistics
like "receives 2 billion pieces of mail a day and 80% is spam".

Think of it like a host with multiple A records - if one A goes down, they
*do* stop trying that one, but they then fail to use backoff on the OTHER
addresses.... ;)
-- 
				Valdis Kletnieks
				Computer Systems Senior Engineer
				Virginia Tech

Attachment: pgp00008.pgp
Description: PGP signature




Discussion Communities


About Merit | Services | Network | Resources & Support | Network Research
News | Events | Contact | Site Map | Merit Network Home


Merit Network, Inc.