OCSP
OCSP (Online Certificate Status Protocol, RFC 6960) lets clients query certificate revocation status in real time, replacing CRL downloads.
Purpose
It lets TLS clients check online whether a certificate has been revoked—more timely and bandwidth-friendly than CRLs.
Mechanism
The client sends an HTTP POST with the certificate serial number to the OCSP responder, which returns a signed good/revoked/unknown status with the signing time. The client verifies the responder's signature.
Use cases
- TLS certificate revocation checks
- CA revocation queries
- Certificate status validation
Related tools
HTTP Status Codes
Reference table of common HTTP status codes (1xx-5xx) with names, categories, and descriptions. Free, private, and 100% client-side. TOOL
URL Parser
Parse a URL into its components: protocol, host, path, query, hash, port, username, and password. Free, private, and 100% client-side. TOOL