TLSversion

TLSversion refers to the version of the Transport Layer Security protocol used to secure a network connection. The version affects the handshake messages, key exchange, encryption algorithms, and integrity checks that protect the session.

TLS has evolved from SSL through several versions. The main publicly deployed versions are TLS 1.0, 1.1, 1.2, and 1.3. TLS 1.0 and 1.1 are deprecated in many environments due to weaker security. TLS 1.2 is still common and supports a wide range of cipher suites. TLS 1.3, defined in RFC 8446, offers stronger security, reduced handshake latency, and a streamlined set of cryptographic primitives. It removes many legacy features such as certain key exchanges and renegotiation.

Version negotiation typically occurs during the TLS handshake. In versions prior to 1.3, the client and server negotiate a version via a protocol version field. In TLS 1.3, the client advertises supported_versions, and the server selects the negotiated version; the 1.3 handshake also handles cipher suites differently and often uses early data with associated risks.

Practically, TLSversion is configured on servers and clients to enforce minimum and maximum supported versions. Security assessment tools report supported versions to gauge exposure. Best practice is to enable TLS 1.2 or 1.3 and disable older versions to minimize risk.