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national security information (NSI)

Abbreviation(s) and Synonym(s):

classified national security information
NSI

Definition(s):

  Information that has been determined pursuant to Executive Order 12958 as amended by Executive Order 13292, or any predecessor order, or by the Atomic Energy Act of 1954, as amended, to require protection against unauthorized disclosure and is marked to indicate its classified status.
Source(s):
FIPS 200 under NATIONAL SECURITY INFORMATION
NIST SP 800-18 Rev. 1 under National Security Information
NIST SP 800-60 Vol. 1 Rev. 1 under National Security Information
NIST SP 800-60 Vol. 2 Rev. 1 under National Security Information
NIST SP 800-53A Rev. 4 [Superseded] under National Security Information

  Information that has been determined pursuant to Executive Order (E.O.) 13526 or any predecessor order to require protection against unauthorized disclosure and is marked to indicate its classified status when in documentary form.
Source(s):
NIST SP 800-37 Rev. 2 under classified national security information
NIST SP 800-53 Rev. 5 under classified national security information from E.O. 13526
CNSSI 4009-2015 [Superseded] under classified national security information from E.O. 13526

  See classified national security information.
Source(s):
CNSSI 4009-2015 [Superseded]