Defense Information Infrastructure

The Defense Information Infrastructure (DII) is embedded within and deeply integrated into the NII. Their seamless relationship makes distinguishing between them difficult. The DII is the shared or interconnected system of computers, communications, data applications, security, people, training, and other support structures serving DOD local, national, and worldwide information needs.

The DII connects DOD mission support, C2, and intelligence computers through voice, telecommunications, imagery, video, and other multimedia services. It provides information processing and services to subscribers over the Defense Information Systems Network. It includes C2, strategic, tactical, intelligence, and commercial communications systems used to transmit DOD information.