The following figure depicts the configuration in which a host is communicating with an encrypting gateway that receives packets from an encrypting nomadic system.
A nomadic encrypting gateway is an encrypting gateway that encrypts and decrypts packets from hosts whose IP address is not known ahead of time (for instance, hosts who receive the IP address dynamically). This is the same as configuring a host-to-host configuration except that the ACL does not have a specific address for the nomadic system. The address in the ACL is * and gets the temporary address from the nomadic system when it contacts the host. The host can only contact the nomadic system when it knows its address. Every time the nomadic system moves and then reconnects with the host, it will have a new address.