nanog mailing list archives
Re: Remote email access
From: "John R Levine" <johnl () iecc com>
Date: 4 Feb 2003 13:50:14 -0500
Blocking "direct-from-dialup" spam is best done on the receiving end, blocking *unauthenticated* SMTP connections made directly from dial-up IPs.
If there were a definitive list of dialup and DHCP IP ranges, I might agree. But after some years of compiling the MAPS DUL, Pan Am's PDL, the osirusoft list, and who knows how many others, there isn't, so I don't see how that's a practical approach. Blocking outbound SMTP also prevents relay exploits of unsecured servers that will never be secured, and there'll never be a definitive list of them, either.
IMHO, to block ALL outbound port 25 traffic on the sending end is throwing the baby out with the bathwater.
It certainly is, but for most ISPs, there's a very small baby in a huge tub of spam. Remember that this whole question only occurs for dialup or DHCP users who are not using their ISP's mail service. While that probably includes just about everyone you and I know, overall, it's a teensy minority of ISP customers. Regards, John Levine, johnl () iecc com, Primary Perpetrator of "The Internet for Dummies", Information Superhighwayman wanna-be, http://iecc.com/johnl, Sewer Commissioner "A book is a sneeze." - E.B. White, on the writing of Charlotte's Web
Current thread:
- Re: Remote email access, (continued)
- Re: Remote email access E.B. Dreger (Feb 04)
- RE: Remote email access Al Rowland (Feb 04)
- Re: Remote email access David Lesher (Feb 04)
- RE: Remote email access Al Rowland (Feb 04)
- Re: Remote email access David Lesher (Feb 04)
- Re: Remote email access Dave Crocker (Feb 04)
- Re: Remote email access David Lesher (Feb 04)
- Re: Remote email access John R. Levine (Feb 04)
- Re: Remote email access Andy Walden (Feb 04)
- Re: Remote email access Jack Bates (Feb 04)
- Re: Remote email access John R Levine (Feb 04)
- Re: Remote email access Andy Walden (Feb 04)
- Re: Remote email access John R Levine (Feb 04)
- Re: Remote email access Dave Crocker (Feb 04)
- Re: Remote email access John R Levine (Feb 04)
- Re: Remote email access Dave Crocker (Feb 04)
- Re: Remote email access Michael . Dillon (Feb 05)
- Re: Remote email access Valdis . Kletnieks (Feb 05)
- Re: Remote email access Jeff S Wheeler (Feb 05)
- Re: Remote email access Dave Crocker (Feb 05)
- WorldCom's DWDM capabilities/OC12 SONET vs DWDM Max's Lists (Feb 05)
- Re: WorldCom's DWDM capabilities/OC12 SONET vs DWDM David Barak (Feb 06)
- Re: WorldCom's DWDM capabilities/OC12 SONET vs DWDM Max's Lists (Feb 27)
- Re: WorldCom's DWDM capabilities/OC12 SONET vs DWDM Daniel Concepcion (Feb 27)