What is Mobile IP?

Mobile IP is a communications protocol developed by the Internet Engineering Task Force. The design of this IETF protocol is configured to make it possible for consumers who use mobile communication devices to be able to move from one network to another, without having to make a change in their IP address. The function of Mobile IP allows the forwarding of Internet traffic to the mobile device even when the device is not connected to the home network.

The creation of Mobile IP meant a significant change in the way information terminates across the Internet. Generally, the routing of information depends on relaying data to IP addresses that are considered fixed in location. With the advent of Mobile IP, this all changed. Instead of basing the termination on a fixed location associated with an IP address, the protocol calls for delivery of data to an IP address that may or may not be currently connected through the mother or home network.

Still, the assignment of a home address on a home network is necessary to ground the mobile device. However, the addition of this protocol makes it possible to also establish what is known as a care-of address. This essentially works in a manner similar to the forwarding of snail mail when a homeowner is going to be out of town for an extended period of time. The care-of address is a temporary means of identifying the current location of the mobile user and the associated IP address, then using the Internet to forward information to that temporary point of termination. With each move to another network, the process assigns a new care-of address, just as a traveler moving from one city to another would establish a new physical forwarding address.

With more people making use of handheld devices to access the Internet and handle emails, business correspondence, and other functions that used to be the province of the desktop computer, Mobile IP has becoming increasingly important. Service providers continue to refine the process, making the use of Mobile IP more attractive to a wider range of customers.