Jos Antonio Garc a-Mac as and Leyla Toumi
The Internet has been around for more than three decades now. A key factor for its longevity is its flexibility to incorporate new technologies. However, this is not always a seamless process, as some of these new technologies break the basic assumptions under which the Internet works. For instance, the Internet was born at a time when all nodes in a network were fixed devices. Therefore, all the basic protocols were designed assuming that the end-points would stay fixed. Obviously, with the recent arrival of mobile networking devices (PDAs, laptops, 3G phones, etc.), these assumptions no longer hold.
We will discuss the problem of mobility in IP networks, with a special emphasis on the case of mobility within a restricted geographical span, also called micro-mobility. Before addressing the problem of local IP mobility, we will examine the technologies that allow local connectivity, so-called "last-meter" technologies such as 802.11 (WiFi), Bluetooth, and HiperLan.