NIPRNet

The Non-classified Internet Protocol (IP) Router Network (abbreviated as "NIPRNet," but commonly written "NIPRNET"), but prevalently referred to as the "Non-classified IP Router Network," is used to exchange sensitive but unclassified information between "internal" users as well as providing users access to the Internet. NIPRNet is composed of Internet Protocol routers owned by the United States Department of Defense (DOD). It was created in the 1980s and managed by the Defense Information Systems Agency (DISA) to supersede the earlier MILNET. NIPRNET is the largest private network in the world. Over the last decades it has grown faster than the U.S. Department of Defense can monitor, which is why DoD spent $10 million in 2010 to map out the current state of the NIPRNET, in an effort to analyze its expansion, and identify unauthorized users, who are suspected to have quietly joined the network. The NIPRNET survey, which uses IPSonar software developed by Lumeta Corporation, also looked for weakness in security caused by network configuration. The Department of Defense has made a major effort over the last few years, to improve network security. The Pentagon announced it was requesting $2.3 billion in the 2012 budget to bolster network security within the Defense Department and to strengthen ties with its counterparts at the Homeland Security Department.

SIPRNet and NIPRNet are referred to colloquially as sipper-net and nipper-net (or simply sipper and nipper), respectively.