Common Access Card (CAC)

Definition

DoD-issued smart card enabling PKI authentication for system access.

Technical Details

A Common Access Card (CAC) is a smart card issued by the Department of Defense (DoD) that supports Public Key Infrastructure (PKI) authentication. It contains an embedded microprocessor and is used for secure access to physical and digital resources. The CAC includes certificates for encryption, digital signatures, and user identification, enabling secure logins to systems and networks. It uses various cryptographic protocols to ensure data integrity and confidentiality, and it can also be used for signing documents and encrypting emails.

Practical Usage

The CAC is utilized by military personnel, civilian employees, and contractors to access DoD systems and facilities. It is commonly used in secure environments such as military bases and government offices, where it serves as a multifactor authentication tool. Users must insert their CAC into a card reader and enter a Personal Identification Number (PIN) to authenticate their identity. Additionally, the CAC is often employed for secure email communications and access to classified information systems.

Examples

• A military service member uses their CAC to log into a secured military information system to access personnel records.
• A civilian employee at the DoD uses their CAC to sign digital documents, ensuring that they are authenticated and the documents are tamper-proof.
• A contractor accesses a secure facility by presenting their CAC, which is scanned at the entrance to verify their identity and clearance level.

Related Terms