The NTSWG, formerly known as the Telecommunications Security Group (TSG), is a Joint Working Group of the Committee on National Security Systems (CNSS) which was established under EO 13231 to protect National Security Systems.
The TSG issued "standards" as the primary technical and policy resource for all aspects of the Technical Surveillance Countermeasures (TSCM) Program within the U.S. Intelligence Community.
The TSG "standards" contain guidance involving telephone systems located in areas where sensitive government information is discussed, processed, and stored, however the implementation of these "standards" does not preclude the application of more stringent requirements and may not satisfy the requirements of other security programs such as TEMPEST, COMSEC, or OPSEC.
The previously issued TSG "standards" are transitioning to CNSS instructions, which provide guidance and establish technical criteria for specific national security systems issues. These instructions include technical or implementation guidelines, restrictions, doctrines, and procedures applicable to information assurance. All instructions are binding upon all U.S. Government departments and agencies.
Note: The TSG "standards" will not be available or valid when replaced by a CNSS instruction.- TSG STANDARD 1
- Introduction to Telephone Security, dated March 1990
- TSG STANDARD 2
- TSG Guidelines for Computerized Telephone Systems, dated March 1990
- NTSWG STANDARD 2a
- NTSWG Guidelines for Computerized Telephone Systems Supplemental, dated March 2001
- NTSWG STANDARD 2b (Superseded by CNSSI-5000)
- NTSWG Guidelines for Voice Over Internet Protocol (VoIP) Computer Telephony, dated April 2006
- TSG STANDARD 3
- Type-Acceptance Program for Telephones used with the Conventional Central Office Interface, dated March 1990
- TSG STANDARD 4
- Type-Acceptance Program for Electronic Telephones used in Computerized Telephone Systems, dated March 1990
- TSG STANDARD 5
- On-Hook Telephone Audio Security Performance Specification, dated March 1990
- TSG STANDARD 6
- Telephone Security Group Approved Equipment, dated March 1990; updated June 2006
- TSG STANDARD 7
- TSG Guidelines for Cellular Telephones, dated September 1994
- TSG STANDARD 8
- Microphonic Response Criteria for Non-communications Devices, dated October 1994
To obtain an issuance not offered in the CNSS Library, refer to our Contact List for more information.