This is a potential security issue, you are being redirected to https://csrc.nist.gov.
Telecommunications services that are used to maintain a state of readiness or to respond to and manage any event or crisis (local, national, or international) that causes or could cause injury or harm to the population, damage to or loss of property, or degrade or threaten the national security or emergency preparedness posture of the United States.
NIST SP 800-18 Rev. 1
[Superseded] under national security emergency preparedness telecommunications services from 47 C.F.R., Part 64 Appendix A
NIST SP 800-53 Rev. 4 [Superseded] from 47 C.F.R., Part 64 Appendix A