Short for DNS Based List, DNS Blacklist, or
DNS Blocklist.
A published list of IP addresses that can be queried through the
Internet. DNSBLs are used to publish
IP addresses associated with
e-mailspam and spamming. Most mail servers can be
configured to reject messages from addresses on a DNSBL. An address found in a
DNSBL may be directly associated with spam, or may have made the list due to
Web server vulnerabilities that can be used by
spammers. There are many DNSBLs available, each published and maintained by
different individuals and organizations.
Open Relay Database A non-profit organization which stores IP addresses of verified open SMTP relays.
SORBS - Fighting spam by finding and listing exploitable servers. The Spam and Open Relay Blocking System (SORBS) was conceived as an anti-spam project where a daemon would check "on-the-fly", all servers from which it received email to determine if that email was sent via various types of proxy and open-relay servers.
