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    Glossary
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ATO

Abbreviations / Acronyms / Synonyms:

Approval to Operate
Authority to Operate
Authorization to Operate

Definitions:

  seeCertificationandAccreditation.
Sources:
NIST SP 800-16 under Approval to Operate

  Authorization to Operate; One of three possible decisions concerning an issuer made by a Designated Authorizing Official after all assessment activities have been performed stating that the issuer is authorized to perform specific PIV Card and/or Derived Credential issuance services.
Sources:
NIST SP 800-79-2

  The official management decision issued by a designated accrediting authority (DAA) or principal accrediting authority (PAA) to authorize operation of an information system and to explicitly accept the residual risk to agency operations (including mission, functions, image, or reputation), agency assets, or individuals.
Sources:
CNSSI 4009-2015 under approval to operate