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

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The RF Network

Computer networks are now able to utilise a variety of wireless connection technologies. In this chapter we are interested in wireless connectivity that facilities portable or mobile computing, although our main interest is in wide-area (cellular) solutions. An increasingly diverse range of wireless solutions provides users with potentially ubiquitous access to services, including the Internet. As already discussed throughout this book, the evolution of internet-orientated software technology, like J2EE, XML and Web Services are helping to make the Internet become an incredibly powerful delivery mechanism for services. The IP network, including the Web 2.0 platform and underlying web-centric services, clearly has much strength as a means to deliver software services, an assertion amply discussed in this book. It is time to look at how we achieve the wireless freedom needed to make these services mobile.

Continuous wireless access to the Internet is now possible on a wide scale thanks to cellular networks. Providing a cellular connection with IP compatibility has been possible since the 2G networks, like GSM. However, the 2G infrastructure and its technical roots grew from the need to talk, not the need to exchange data. These early data connections were not packet-orientated, so they were very inefficient for carrying IP data. Attempts were made to overlay a packet access method on the 2G networks and this became the basis for 2.5G, otherwise known as General ...