What is a key function of a Certificate Authority (CA)?

A Certificate Authority (CA) plays a crucial role in the management of public key infrastructure (PKI) by establishing a link between entities and their public keys. This is accomplished through the issuance of digital certificates, which serve as electronic credentials. The digital certificate contains the entity's public key along with identifying information about the entity, and it is digitally signed by the CA to ensure its authenticity.

This process allows users and systems to trust that the public key indeed belongs to the entity stated in the certificate. When a user receives a digital certificate, they can verify the signature of the CA using the CA's own public key. If the signature is valid, the user can be assured of the association between the entity and its public key. This trust framework is fundamental for secure communications and transactions over the internet, enabling functionalities such as SSL/TLS for secure web browsing and electronic signatures for verifying the authenticity of messages and documents.

Understanding the primary function of a Certificate Authority helps in recognizing its importance in cybersecurity and digital communication, where the integrity and authenticity of data and entities are paramount.