Question: When a Transport Layer Security (TLS) client is removed from a telecommunications network, what action should the operator take regarding the TLS client's certificate to ensure security?
Option 1: Update the TLS client's certificate to reflect a new expiration date
Option 2: Remove all mentions of the TLS client from the network's authentication logs
Option 3: Temporarily store the TLS client's certificate for potential future use
Option 4: List the TLS client's certificate in the Certificate Revocation List (CRL) or utilize Online Certificate Status Protocol (OCSP) servers
Explanation: When a TLS client is removed from the network, to maintain security and prevent potential misuse of the client's credentials, the operator must ensure that the client can no longer authenticate. Listing the TLS client's certificate in the CRL or using OCSP servers effectively revokes the certificate, notifying the network that the client is no longer trusted or valid, thus terminating any existing TLS connections securely.