There are several distinguishing characteristics of the mobile Internet. In this chapter, the focus is on both packet-switched public networks (i.e. the fixed Internet extended to mobile devices through data transports that support IP, the Internet Protocol) and connection-based air interfaces that can transport XML-based messaging (e.g. GSM, GPRS and 3rd generation wireless technologies). In particular, there are severe limitations to the availability of a connection, high and unpredictable round-trip time for requests and responses (latency), and limited bandwidth.
What makes the mobile Internet so interesting? The position of the mobile terminal can be used in many ways to personalize and adapt the behavior of an application to meet the needs and expectations of the user in a very direct way. Technologies to determine the position of a terminal are evolving rapidly. Handset manufacturers and wireless operators in North America and Western Europe face increasingly stringent government requirements to provide the location of the mobile terminal to emergency service providers in the case of calls made to emergency numbers such as 911 and 112.