How do digital certificates function within a public key infrastructure (PKI)?

Digital certificates play a crucial role in public key infrastructure (PKI) by validating the ownership of public keys. In a PKI system, each entity (such as a person, organization, or device) is issued a digital certificate by a trusted certificate authority (CA). This certificate contains the entity's public key along with information such as the entity's identity and the CA's digital signature, which helps affirm the authenticity of the information.

When someone wants to establish a secure connection or validate a signature, they can use the digital certificate to ensure that the public key contained within truly belongs to the entity it claims to represent. This validation process helps prevent attacks like man-in-the-middle, where an attacker could impersonate a legitimate entity by sending a counterfeit public key.

In summary, by confirming the ownership of public keys, digital certificates enable secure communication and transactions in a PKI environment, fostering trust between parties in digital interactions.