Introducing mobility into a communications environment that was initially designed for fixed nodes brings up many challenges that come from a technical as well as from a security point of view. The challenges posed by introducing mobility for seamlessly roaming between IP networks are addressed by the MobileIP standard. This chapter describes the solution proposed by MobileIP with a focus on the security mechanisms used in version 6 of this protocol.

11.1 Introduction

Mobility is an increasing trend in today's computing environments. Environments that were not designed to be mobility-aware are now faced with the challenge of adapting to a more mobile world. The Internet is a key example of such a global communications environment where mobile devices like laptops and PDAs can already operate as nodes while devices such as watches, cars and home appliances are likely to connect in the near future. However, the Internet was originally designed for fixed nodes. Connecting mobile devices to it was not an envisioned development direction at the moment of the design and its initial deployment. Therefore, using the standard Internet stack of protocols for connecting mobile devices to the Internet would limit their mobility.

The IP address assigned to each node is used for identifying the peers of a connection. The routing mechanisms on the Internet use the IP address in order to deliver packets to the right destination. For more information on the inner workings of the Internet, like the IP...