Home page logo

nanog logo nanog mailing list archives

Re: Stealth Blocking
From: "Eric A. Hall" <ehall () ehsco com>
Date: Thu, 24 May 2001 10:23:23 -0700

Dave Rand wrote:

I'm not sure how effective rate limiting will be.  Many spammers send
one copy of the spam to an open relay, but use many (2 to 50)

Rate-shapers would also work on the relays. The idea is that if ISPs would
implement a default rate-limit (let's say 4kb/s) that it wouldn't
interfere with normal use. It would interfere with spam distribution
because it would slow down the big runs dramatically.

The negative side effect is that it cripples people who use email as a
file transfer protocol.

One other way to do this might be to do port 25 blocking on new
customers, but allow customers to get unblocked on request after
they have been  around a while...

That would be nice as well and is something I've advocated. ISPs seem
unwilling to do this, and it would seem that implementing a default
low-bandwidth rate limit would mean less maintenance.

Eric A. Hall                                        http://www.ehsco.com/
Internet Core Protocols          http://www.oreilly.com/catalog/coreprot/

  By Date           By Thread  

Current thread:
[ Nmap | Sec Tools | Mailing Lists | Site News | About/Contact | Advertising | Privacy ]