ISAKMP (Internet Security Association and Key Management Protocol) is a protocol for establishing Security Associations (SA) and cryptographic keys in a internet environment.
ISAKMP defines the procedures for authenticating a communicating peer, creation and management of Security Associations, key generation techniques, and threat mitigation (e.g. denial of service and replay attacks).
ISAKMP typically utilizes IKE for key exchange, although other methods can be implemented.
ISAKMP is documented in RFC 2048: Internet Security Association and Key Management Protocol (ISAKMP).
ISAKMP under IP (Internet Protocol) is documented in RFC 2407: The Internet IP Security Domain of Interpretation for ISAKMP.