Simple definition
Protocol for verifying the revocation status of a certificate.
Technical definition
The procedure for verifying the revocation status of a certificate is generally integrated with other services in a professional environment to determine quickly whether a certificate has been issued. revoked before its expiry date.
What is it used for?
whether a certificate has been revoked before its expiry date.
Practical example
a browser questions an answering machine OCSP to verify the certificate of a site.
Common issues
- expired certificate or name not covered
- incomplete confidence chain
- wrong key, revocation or automation of renewal
Key takeaway: Always adapt the diagnosis to the product version and the architecture actually deployed.