Mobile Internet Access

Abstract

The first half of this century has seen the development of a public wireline network that allows reliable and affordable communication of voice and low bitrate data around the globe. There is also a multiplicity of specialized wired networks optimized for special purposes such as high-speed communications in the local networks. Since the mid-eighties, the Internet (a wireline data network of computers connected across the globe) has seen considerable growth in the number of hosts. Estimates are that 30–40 million users world-wide are connected to the Internet, with this total doubling every year. An increasing number of these users are mobile, as evidenced by increasing sales of laptop/ notebook computers. While this increase in the user base is welcomed, it adds the increasing burden of providing mobility across the Internet. Even when the physical infrastructure for the ubiquitous network connectivity will be available, there are several problems the mobile users must overcome to make full use of it. The mobile hosts must be able to move seamlessly between networks in different administrative domains as they move around the network, and they must also be able to change between different networks to achieve the best possible connectivity wherever they are located.