What is the primary purpose of Public Key Infrastructure (PKI)?

The primary purpose of Public Key Infrastructure (PKI) is to manage and provision asymmetric keys and certificates. PKI facilitates secure communications and transactions over the internet by enabling secure key exchange and authentication through a structured system of digital certificates. These certificates validate the identity of parties involved in the communication, ensuring that the entities are who they claim to be.

Asymmetric key pairs, consisting of a public key and a private key, are central to PKI’s functionality. The public key can be shared openly, allowing others to encrypt messages intended for the key owner. Conversely, the private key remains confidential and is used to decrypt the received messages. PKI not only supports encryption but also incorporates digital signatures, which verify the authenticity of the data and the identity of the sender.

In contrast to the other options, they do not align with the fundamental roles of PKI. While symmetric keys can be used for encryption, they do not pertain to the PKI framework, which relies on asymmetric cryptography. Setting firewall rules is related to network security and not the key management aspect of PKI. Finally, physical security measures address the protection of physical assets, which is outside the scope of PKI’s digital focus.