Common Access Card (CAC) The CAC, a "smart" card about the size of a credit card, is the standard identification for active duty uniformed Service personnel, Selected Reserve, DoD civilian employees, and eligible contractor personnel. It is also the principal card used to enable physical access to buildings and controlled spaces, and it provides access to DoD computer network and systems.

Personal Identity Verification (PIV) A PIV credential is a U.S. federal government-wide credential used to access federally controlled facilities and information systems at the appropriate security level. PIV credentials have certificates and key pairs, pin numbers, biometrics like fingerprints and pictures, and other unique identifiers. When these items are put together in a PIV credential, the credential provides the capability to implement multifactor authentication for networks, applications, and buildings.

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