Key exchange is a cryptographic procedure by which two parties establish a shared secret over an insecure channel for use in subsequent encrypted communication.
Semantic Classification
Content
- Key exchange protocols allow two parties to agree on a shared key without transmitting the key itself. The Diffie-Hellman protocol does this using modular exponentiation, and elliptic curve variants achieve the same with smaller keys.
- The agreed key is typically used for symmetric encryption of the session. Authenticated key exchange combines this with identity verification to resist interception by an active attacker.