Cisco Systems 78-11741-02 Configuring Mobile IP, Mobile IP Overview, Why is Mobile IP Needed?

Configuring Mobile IP

This chapter describes how to configure Mobile IP. For a complete description of the Mobile IP commands in this chapter, refer to the “Mobile IP Commands” chapter of the Cisco IOS IP Command Reference, Volume 1 of 3: Addressing and Services. To locate documentation of other commands that appear in this chapter, use the command reference master index or search online.

Mobile IP Overview

If an IP node, for example, a personal digital assistant (PDA), moves from one link to another, the network prefix of its IP address no longer equals the network prefix assigned to its current link. As a result, packets are not delivered to the current location of the PDA.

Mobile IP enables an IP node to retain the same IP address and maintain existing communications while traveling from one link to another.

Mobile IP is an IETF standards based solution for mobility at the network layer, which is Layer 3. Mobile IP supports the following RFCs:

•RFC 2002, IP Mobility Support

•RFC 2003, IP Encapsulation within IP

•RFC 2005, Applicability Statement for Mobile IP

•RFC 2006, The Definitions of Managed Objects for IP Mobility Support

To identify the hardware platform or software image information associated with a feature, use the Feature Navigator on Cisco.com to search for information about the feature or refer to the software release notes for a specific release. For more information, see the “Identifying Supported Platforms” section in the “Using Cisco IOS Software” chapter in this book.

Why is Mobile IP Needed?

New devices and business practices, such as PDAs and the next-generation of data-ready cellular phones and services, are driving interest in the ability of a user to roam while maintaining network connectivity. The requirement for data connectivity solutions for this group of users is very different than it is for the fixed dialup user or the stationary wired LAN user. Solutions need to accommodate the challenge of movement during a data session or conversation.

Cisco IOS IP Configuration Guide

IPC-159