ClientHelloviestillä
ClientHelloviestillä, or the ClientHello message, is the initial handshake message sent by a TLS client to a server to begin a secure connection. It advertises the client’s protocol versions, cryptographic capabilities, and other parameters that will shape the ensuing handshake and session keys. The server uses this information to decide on the protocol version and cipher suite for the session and to determine what extensions, if any, it will support.
In TLS 1.2 and earlier, the ClientHello typically contains a legacy_version field, a 32‑byte random value, a
Security and privacy implications accompany the ClientHello. Because most of its payload is sent in the clear
Overall, the ClientHelloviestillä is a core element of the TLS handshake, enabling the secure negotiation that