Today I went through the “Finally blocking some spam” titled conversation on the postfix mailing list. While I do not like the main idea of this discussion at all, e.g. blocking SMTP connections on the firewall level by whole IP country blocks, there are several interesting links:
- invaluement DNS BL
Another BL which claims to blocking 40% of connections *after* zen and spamcop. Though, costs money.
URL: http://dnsbl.invaluement.com/ - The South Korean Network Blocking List
URL: http://korea.services.net/ - Greylisting: The Next Step in the Spam Control War
Evan Harris is an enthusiastic GrayListing fan (as I am too). This page is devoted to promote and to explain GrayListing.
URL: http://projects.puremagic.com/greylisting/ - Unlisting – Port Knocking for SMTP
Unlisting is another technique to fight SPAM.
URL: http://unlisting.org/ - Nolisting – Poor Man’s Greylisting
And another greylisting option.
URL: http://nolisting.org/ - Country IP Blocks: Network Allocations by Country with Searchable IP Database
Nice … I suspect this is something like GeoIP but free – and updated every 2 hours.
URL: http://www.countryipblocks.net/index.php - policyd-weight – A policy daemon for Postfix
URL: http://www.policyd-weight.org/ - UCEPROTECT®-Network Project
URL: http://www.uceprotect.net/en/index.php - backscatterer.org
Backscatter BL
URL: http://www.backscatterer.org/
Another anti SPAM solution again