Who issues digital certificates in a PKI system?

In a PKI system, digital certificates are issued by Certificate Authorities (CAs). CAs are trusted entities responsible for verifying the identities of individuals, organizations, or devices before issuing digital certificates. This process includes checking the credentials and ensuring that the information provided is valid and accurate. The CA signs the certificate using its private key, which establishes a chain of trust in the PKI framework; users can then trust the certificates issued by that CA.

By issuing digital certificates, CAs enable secure communications, encryption, and authentication processes essential for maintaining the integrity and confidentiality of data exchange across networks. Their role is critical because it helps establish a reliable and trusted digital environment, which is foundational in various applications such as secure email, online transactions, and identity verification.

Other options mentioned, such as Registration Authorities, serve different functions within a PKI system, such as facilitating the registration process but do not issue certificates themselves. End users and system administrators are typically the recipients or users of these certificates rather than issuers.