- DISN : Add brief definition or description
- Military communications : Add brief definition or description -->
- Compartmented control system : A set of controls, in addition to a regular national security classifications, that adds additional security restrictions to especially sensitive information
- Defense Information Systems Agency : U.S. Department of Defense organization with overall responsibility for shared strategic communications networks as well as global information systems infrastructure and multiple agency applications
- Defense Intelligence Agency : One of the members of the United States intelligence community, charged with providing national-level analysis specifically relevant for military needs, and being the focal point for measurement and signature intelligence
- Joint Chiefs of Staff : The staff committee of the most senior members of the U.S. military services, charged with policy advice, doctrinal development, and preparedness rather than operational control of forces
- National Security Agency : An organization within the United States Department of Defense, with the dual roles of the principal signals intelligence agency in the United States intelligence community, but also having the responsibility for information assurance of military, diplomatic, and other critical communications.
- NIPRNET : The common user network intended to carry U.S. military "sensitive but unclassified" traffic for military personnel, government employees, military contractors, and approved allies
- Sensitive Compartmented Information Facility : A work area with the administrative, physical, and electronic safeguards to allow proper protection of information or materials under the requirements of a compartmented control system
- SIPRNET : The shared United States Department of Defense network that carries the bulk of classified information, limited to a security classification of SECRET.
- Special Security Office : Within a military command, the staff function, sometimes including a SCIF or other secure working area, which is responsible for ensuring the security of information covered by compartmented control systems
- TACLANE : A family, designated TSEC/KG-175, of bulk encryption devices specified by the National Security Agency, which work with high-speed IEEE 802.3/Ethernet interfaces
- TROJAN SPIRIT : A U.S. military communications system for handling the most highly classified intelligence information in field headquarters, which also provides field units with connectivity to worldwide high-security networks
- TSQ-226 : Mobile earth station of the TROJAN SPIRIT LITE intelligence communications satellite system