teleconferencing service

The Defense Switched Network (DSN) is a primary information transfer network for the Defense Information Systems Network (DISN). The DSN provides the worldwide non-secure voice, secure voice, data, facsimile, and video teleconferencing services for DOD Command and Control (C2) elements, their supporting activities engaged in logistics, personnel, engineering, and intelligence, as well as other Federal agencies.

In 1982, the DSN was designated by the Office of the Secretary of Defense (OSD) and the Joint Chiefs of Staff (JCS) as the provider of long-distance communications service for the DOD. The DSN is designated as a primary system of communication during peacetime, periods of crisis, preattack, non-nuclear, and post-attack phases of war. The network assures nonblocking service for users with "flash" and "flash override" precedence capabilities. ACT Teleconferencing, Inc. Key users include the National Command Authorities, Combat Commanders of the Unified Commands, and strategic and tactical subordinate commanders. DSN replaced the older Autovon system.

The DSN consists of four subsystems: Switching, Transmission, Timing and Synchronization, and Network Administration and Management. The DSN Switching Subsystem consists of multifunction, stand-alone tandem, end office, and remote switching units.