nanog mailing list archives
Re: How do you stop outgoing spam?
From: Brad Knowles <brad.knowles () skynet be>
Date: Tue, 17 Sep 2002 18:30:36 +0200
At 10:26 AM -0700 2002/09/15, Dave Crocker wrote:
2. The issue with email is authentication, not privacy. Authentication can be achieved can be achieved easily over port 25, without encryption. Hence, blocking port 25 blocks legitimately validated email, as well as possible spam.
True enough. However, there are no intelligent transparent proxies that I know of which will allow authenticated and/or link-encrypted port 25 connections through to the indicated site, and shunt the non-authenticated/non-encrypted sessions to the side. Since this information is only available at the IP level, this is not something you can fix inside the SMTP MTA -- the critical information is destroyed before then.
I imagine if you could get cisco (and other vendors) to fix their transparent proxy server software to be more intelligent, that would fix the problem.
-- Brad Knowles, <brad.knowles () skynet be> "They that can give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety." -Benjamin Franklin, Historical Review of Pennsylvania. GCS/IT d+(-) s:+(++)>: a C++(+++)$ UMBSHI++++$ P+>++ L+ !E W+++(--) N+ !w--- O- M++ V PS++(+++) PE- Y+(++) PGP>+++ t+(+++) 5++(+++) X++(+++) R+(+++) tv+(+++) b+(++++) DI+(++++) D+(++) G+(++++) e++>++++ h--- r---(+++)* z(+++)
Current thread:
- Re: How do you stop outgoing spam?, (continued)
- Re: How do you stop outgoing spam? Paul Vixie (Sep 10)
- Re: How do you stop outgoing spam? Brad Knowles (Sep 11)
- Re: How do you stop outgoing spam? Barry Shein (Sep 10)
- Re: How do you stop outgoing spam? Brad Knowles (Sep 11)
- Re: How do you stop outgoing spam? David Charlap (Sep 11)
- Re: How do you stop outgoing spam? Stephen J. Wilcox (Sep 11)
- Re: How do you stop outgoing spam? Brad Knowles (Sep 11)
- Re: How do you stop outgoing spam? Joel Baker (Sep 11)
- Re: How do you stop outgoing spam? Brad Knowles (Sep 11)
- Re: How do you stop outgoing spam? Christopher X. Candreva (Sep 11)
- Re: How do you stop outgoing spam? Barry Shein (Sep 11)
- Re: How do you stop outgoing spam? Brad Knowles (Sep 17)
- Re: How do you stop outgoing spam? Valdis . Kletnieks (Sep 17)
- Re: How do you stop outgoing spam? Brad Knowles (Sep 17)
- Message not available
- Re: How do you stop outgoing spam? Brad Knowles (Sep 17)
- Re: How do you stop outgoing spam? Valdis . Kletnieks (Sep 10)
- Re: How do you stop outgoing spam? Barry Shein (Sep 10)
- RE: How do you stop outgoing spam? Al Rowland (Sep 10)