Intelligent DNS Threat feed
What domain names map to "this" IP address, now and in the past? When was "this" name first used and by whom? What domain names share this same MX record?
Farsight provides intelligent DNS feeds. At the core of their offering is their proprietary global Internet sensor array.
Farsight’s sensors, which are placed at strategic observation points around the world, are in production networks at Internet service providers (ISPs), Internet exchanges, Internet cloud service operators, prominent social networks, universities, and large corporations.