February 5, 2002
Practical Aspects of Modern Cryptography
48
Online Status Checking
nOCSP: Online Certificate Status Protocol
nA way to ask “is this certificate good right now?
nGet back a signed response from the OCSP server saying, “Yes, cert C is good at time t”
nResponse is like a “freshness certificate”
nOCSP response is like a selective CRL
nClient indicates the certs for which he wants status information
nOCSP responder dynamically creates a lightweight CRL-like response for those certs