nanog mailing list archives
Re: Misguided SPAM Filtering techniques
From: Adrian Chadd <adrian () creative net au>
Date: Tue, 23 Oct 2007 16:28:28 +0800
On Tue, Oct 23, 2007, Dave Pooser wrote:
It seems to me that blocking port 25 by default and unblocking on request would be an ideal low-maintenance solution that would reduce spam considerably, and has the added benefit of being on-topic for NANOG.
For those of you who run Cisco kit; you can also use WCCPv2 to redirect 25/TCP -in hardware path without policy routing- to a farm of servers. Its actually documented in the WCCPv2 specification - you can redirect arbitrary TCP/UDP ports. Think of the possibilities. (I don't think the CRS does WCCP :P but it'll be in hardware path on 6500/7600 on anything >= SUP2/PFC2; 3560/3750/4500/4948; It'll also be in CEF path IIRC on software platforms.) I've done this in my lab at home and it works fine. Whats missing is some glue to handle transparently routed connections once they hit your SMTP farm; I'm quite happy to help people out if anyone is interested (and I'll even put the results in the nanog wiki if people care.) 2c, Adrian
Current thread:
- Re: Misguided SPAM Filtering techniques, (continued)
- Re: Misguided SPAM Filtering techniques Dave Pooser (Oct 22)
- Re: Misguided SPAM Filtering techniques Sean Figgins (Oct 22)
- [admin] Re: Misguided SPAM Filtering techniques Alex Pilosov (Oct 22)
- Re: Misguided SPAM Filtering techniques William Herrin (Oct 21)
- Re: Misguided SPAM Filtering techniques Suresh Ramasubramanian (Oct 21)
- Re: Misguided SPAM Filtering techniques Al Iverson (Oct 22)
- Re: Misguided SPAM Filtering techniques Sean Donelan (Oct 21)
- Re: Misguided SPAM Filtering techniques Adrian Chadd (Oct 23)
- Re: Misguided SPAM Filtering techniques Owen DeLong (Oct 23)
- Re: Misguided SPAM Filtering techniques Jack Bates (Oct 23)
- Message not available
- Re: Misguided SPAM Filtering techniques Owen DeLong (Oct 23)
- Re: Misguided SPAM Filtering techniques Dave Pooser (Oct 23)
- RE: Misguided SPAM Filtering techniques David Schwartz (Oct 23)
- Re: Misguided SPAM Filtering techniques Dave Pooser (Oct 23)