SIPRNET replaces the DDN DSNET1 as the SECRET portion of DISN. Its complete architecture will be achieved by constructing a new worldwide backbone router system. The primary method for secret-level network connectivity is via Base secret-level networks which in turn provide Base Router connectivity to SIPRNET. Various DOD router services and systems will migrate onto the SIPRNET backbone router network to serve the long-haul data transmission needs of the users. Transmission services will use smart multiplexer and 512 kilobits per second (kbps) channels. Other transmission services will be acquired or leased as needed. Future expansion will progress to the T1 circuit data rate of 1.544 Megabits (Mbps) and potentially to the T3 data rate of 45 Mbps. High speed packet switched service will be provided through the use of IP routers. This SECRET router layer of the DISN is intended to support national defense C3I requirements, to include the issuing of COMSEC keys used with the STU-III to make secure dial-up SIPRNET comm server connections.
The Secret Internet Protocol Router Network (SIPRNET) has matured to be the core of our warfighting command and control capability. Many expeditionary commanders ask for SIPRNET ahead of secure voice when deploying their forces. SIPRNET is fast becoming the defacto standard of preferred data services, even over NIPRNET. The SIPRNET is the new, worldwide router-based network replacing the older X.25-based packet switched network (the Defense Secure Network One (DSNET1) of the Defense Data Network (DDN)). The initial SIPRNET backbone router network went online 3 March 1994. Subscribers started coming on line shortly thereafter. The SIPRNET WAN (as of 31 May 1995) consisted of a collection of 31 backbone routers interconnected by high-speed serial links to serve the long-haul data transport needs of secret-level DoD subscribers. Additional SIPRNET backbone routers are being planned to meet increased customer requirements. SIPRNET supports the DoD standard Transmission Control Protocol/Internet Protocol (TCP/IP) protocol service. Subscribers within the DoD and other Government Agencies are able to use the SIPRNET for passing datagrams at the Secret-Not Releasable to Foreign Nationals (SECRET-NOFORN) classification level.
