Red Hat Enterprise Linux supports a protocol for connecting remote hosts and networks to each other using a secure tunnel on a common carrier network such as the Internet. The protocol, called IPsec, can be implemented using a host-to-host (one computer workstation to another) or network-to-network (one LAN/WAN to another). The IPsec implementation in Red Hat Enterprise Linux uses Internet Key Exchange (IKE), which is a protocol implemented by the IETF to be used for mutual authentication and secure associations between connecting systems.
The Red Hat Enterprise Linux implementation of IPsec uses IKE for sharing keys between hosts across the Internet. The racoon keying daemon handles the IKE key distribution and exchange.