Question
What is the primary role of a Certificate Authority (CA)
in a Public Key Infrastructure (PKI)?Solution
A Certificate Authority (CA) is a trusted entity that issues digital certificates after verifying the identity of the certificate holder. These certificates bind the holder’s identity to their public key, ensuring that communications with that entity are authentic and secure. For instance, in HTTPS, the CA ensures that a website claiming to be "example.com" is genuinely operated by the authorized party before issuing a certificate. This verification builds trust between users and the entity they are interacting with. CAs form the backbone of PKI, as they uphold the integrity of digital certificates and enable secure, authenticated communication over the internet. Without this trust, attackers could impersonate legitimate entities, leading to widespread phishing and fraud. Why Other Options Are Incorrect:
- A) Private keys are generated by the certificate requester or their system, not the CA.
- C) Encryption is performed using keys, not by the CA itself.
- D) While CAs maintain Certificate Revocation Lists (CRLs), their primary function is to verify identities, not just manage revocations.
- E) DNS resolution is unrelated to the CA’s role in PKI.
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