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key share

Each side's half of the fresh shared secret, sent in the TLS hellos.

In TLS 1.3, ClientHello and ServerHello each carry a key share -- an ephemeral ECDHE public value -- from which both sides derive the handshake keys.

Examples

  • In the ClientHello, the sensor sends its key share, its half of an ECDHE exchange; the broker replies with its own in the ServerHello.

  • Both key shares cross the network in the clear, yet only the sensor and the broker can compute the shared secret from them.

See also

key agreement certificate chain TLS
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