A Common Access Card
is a credit card-sized smart card used for identification of active-duty military personnel, selected reserve, US Department of Defense (DoD) civilian employees and
eligible contractor personnel. In addition to providing physical access to buildings and protected areas it also allows access to DoD computer networks and systems satisfying two-factor authentication, digital security and data encryption. It leverages
a Public Key Infrastructure (PKI) Security Certificate to verify a cardholder’s identity prior to allowing access to protected resources.