What is the role of a Certificate Authority (CA) in public key infrastructure (PKI)?

The role of a Certificate Authority (CA) in public key infrastructure (PKI) is essential for establishing a trusted environment for secure communications. The primary responsibility of a CA is to issue and manage digital certificates, which serve to verify the identity of entities such as individuals, organizations, or devices within the network.

When a CA issues a digital certificate, it binds a public key to the identity of the certificate holder and provides assurance that the public key contained within the certificate actually belongs to the named entity. This verification process helps to prevent impersonation and man-in-the-middle attacks, as users can trust that they are communicating with the legitimate owner of the public key.

Moreover, the CA is also involved in the lifecycle management of certificates, including renewal, revocation, and validation, which further ensures the security and integrity of communications across the internet. By performing these functions, the CA plays a critical role in facilitating secure transactions and protecting sensitive information exchanged between parties.