Final answer:
In TLS client authentication, properties such as the client's digital certificate, private key, handshake protocol version, and cryptographic algorithms are examined to verify the client's identity and establish a secure connection. Properties like the certificate's subject and EV details, as well as validation through CRL or OCSP, are also checked.
Step-by-step explanation:
Properties Examined in TLS Client Authentication
In TLS (Transport Layer Security) client authentication, several properties are examined to ensure the security and identity of the client connecting to a server. The primary property is the client's digital certificate, which is validated by checking if it is issued by a trusted Certificate Authority (CA), has not expired, and is not revoked. This certificate contains the public key associated with the client, which is used in the handshake process to establish a secure connection. Another property that is examined is the client's private key which, although never transmitted, is used to create a signature that the server can verify using the public key in the client's certificate. Additionally, the handshake protocol version and the cryptographic algorithms supported by the client are also examined, ensuring compatibility and the level of security required for the communication.
Properties such as the certificate's subject and the presence of any Extended Validation (EV) details provide further identity assurance about the client. The server will also check the Certificate Revocation List (CRL) or use the Online Certificate Status Protocol (OCSP) to ensure the client's certificate is still valid. Sometimes, additional authentication factors such as passwords or biometric data could also be requested as part of a multi-factor authentication process.