The Defense Information System Network (DISN) provides secure voice services using the Joint Staff Defense Red Switch Network (DRSN). This global, secure voice service provides the President, Secretary of Defense, Joint Chiefs of Staff, combatant commanders and selected agencies with command and control secure voice and voice-conferencing capabilities up to the Top Secret SCI level.
Department of Defense and federal government agencies that have Joint Staff approval can access the network. Joint Staff policy for obtaining service is in Chairman of the Joint Chiefs of Staff Instruction CJCSI 6215.01, dated November 9, 2007. Upon approval by the Joint Staff, DISA will work with the customer and the appropriate military department to arrange for service.
The DISN also provides Secret only Voice over Secure IP (VoSIP) as an adjunct to the DRSN for users that do not require the full command and control and conferencing capabilities of the DRSN and need only simple Secret level phone service. This service requires Secret IP Router network (SIPRNet) service as transport. Requests for obtaining VoSIP service are governed by CJCSI 6215.01.