IP Location

In the previous chapter, we examined location determination and acquisition techniques that can be applied to enterprise IP networks. In this chapter, we will look at location determination and acquisition techniques for residential broadband networks, and specifically focus on DSL and cable networks.
DSL is the fastest growing technology, enabling the deployment of residential broadband networks globally. By the end of 2005, there were 139 million DSL subscribers worldwide and 48.2 million subscribers in Europe, while China, the Middle East, and Africa all had growth rates above 100 percent. This fantastic growth rate has largely been due to DSL's ability to work over existing copper telephone lines that run to most houses in urban areas throughout the world.
DSL uses special modems at each end of the phone line that make use of the bandwidth available in the wires that is not used for conventional voice traffic. This allows a residence to have high-speed Internet connectivity and a normal telephone service at the same time over the same copper pair. At the telephone exchange, the DSL signal is separated from the voice traffic and ultimately routed through the subscriber's ISP.
Incumbent telephone companies have a preference toward DSL broadband since it enables them to make use of existing copper cables to provide next-generation network access at a fraction of what it would cost to install new purpose-built cable plants (see Figure 6.1).
It should be noted that DSL networks are...