DNS-based blackhole list (e-mail) (DNSBL)
DNS-based Blackhole List (DNSBL) is a real-time queryable blacklist on which emails identified as spam are registered. The DNSBL lists also include the Realtime Blackhole List( RBL).
As the name DNSBL indicates, these blacklists list servers whose domain names are used to send malware, mainly spam, viruses or Trojans. The detection of malware and the listing take place in near real time. The DNSBL lists can be used by mail servers to control incoming e-mails and block e-mails as soon as they detect a critical domain name.