Public Key Infrastructure (PKI)

Public Key Infrastructure (PKI) is the system of digital certificates, certificate authorities, and registration authorities that enables secure electronic communications. In the DoD, PKI is the backbone of identity verification — it's what makes your Common Access Card (CAC) work for authentication, email signing, and document encryption.

DoD PKI uses digital certificates issued to people, systems, and devices to verify identities and protect communications. When you use your CAC to log into a DoD system or digitally sign an email, PKI is the technology making that possible.