The protocol used to set up a security association in the Internet Protocol Security (IPSec) protocol suite. Although IPSec, or IKE (Internet Key Exchange), is an optional part of the IPv4 standard, it is a mandatory part of the new IETF IPv6 standard, which is soon to be adopted throughout the Internet.

The IKE command can perform several functions, including activating, removing, or listing IKE and IP Security tunnels. IKE uses a Diffie-Hellman key exchange to set up a shared secret from which cryptographic keys are derived in a partial implementation of the so-called Oakley protocol. Public key techniques or pre-shared secrets are used to authenticate communicating parties.

See Also: Algorithm; Diffie-Hellman Public-Key Algorithm (DH); Internet Engineering Task Force (IETF); Internet Protocol Security (IPSec); Internet Protocol Version 4 (IPv4) and Internet Protocol Version 6 (IPv6).