2.7 DHCP and Easy IP
2.7.4 Easy IP

Easy IP is a combination of Cisco IOS features that allows a router to negotiate its own IP address and to do NAT through that negotiated address. Typically deployed on a small office/home office (SOHO) router, Easy IP is useful in cases where a small LAN connects to the Internet via a provider that dynamically assigns only one IP address for the entire remote site.

A SOHO router with the Easy IP feature set uses DHCP to automatically address local LAN clients with RFC 1918 addresses. When the router dynamically receives its WAN interface address via the Point-to-Point Protocol, it uses NAT overload to translate between local inside addresses and its single global address. Therefore, both the LAN side and the WAN side are dynamically configured with little or no administrative intervention. In effect, Easy IP offers "plug-and-play" routing.