Carnivore (DCS1000) was a system implemented by the Federal Bureau of Investigation (FBI). It was designed to monitor email and electronic communications by using a customizable packet sniffer that can monitor all of a target user's internet traffic.
Carnivore was the successor of an earlier FBI project "Omnivore", which itself replaced an older surveillance tool migrated from the U.S. Navy. In September 1998, the FBI's Data Intercept Technology Unit (DITU) in Quantico, Virginia, launched a project to migrate Omnivore from Sun's Solaris operating system to a Windows NT. This was done to facilitate the miniaturization of the system and support a wider range of computer equipments. The migration project was called "Phiple Troenix" and the resulting system was named "Carnivore."