Next Generation Wireless Applications: Creating Mobile Applications in a Web 2.0 and Mobile 2.0 World, 2nd Edition

2.5 PHYSICAL NETWORK ELEMENTS

For the rest of this book I shall be aiming to expand on the networks in the model just outlined. I shall do this by discussing either paradigms (essentialised ideas about what a particular network does) or technologies. Figure 2.7 offers an extremely simplified view of some of the more important building blocks that we might expect to encounter as we move across the networks, but I shall offer a much more detailed view later in the book, especially as in my role as an applications architect I am often asked what does the applications ecosystem look like.

The rest of this book will explain how these elements work within the mobile ecosystem, focusing on various levels of detail depending on how relevant the particulars are to our wider concern with mobile applications and services. In some areas, we shall drill down several layers of detail as the technologies involved are very specific to the mobile framework, such as how Java-2 Micro Edition (J2ME) works on the devices and the dynamics and systems issues of loading J2ME programs, called MIDlets, over-the-air (OTA), which means across an IP connection supported by the RF network.

In other areas, like the IP network, we shall focus mainly on the key protocols and security aspects that are essential to understand in any mobile Internet application, but we shall not look into too much detail about the infrastructural workings of an IP network, like the use of routers and so on. The only time we shall ...