Voice Over IP

STEPS TO THE EXCHANGE OF VOIP TRAFFIC

Figure 7-1 represents a summary of several key points made in previous chapters, plus some additional information. It shows the major steps involved in setting up a connection between a user and a service provider. In this example, the service provider is running a router, and the user machine is a native mode VoIP device [configurations (b) or (c) in Figure 1-2, Chapter 1]. Here is a description of each event depicted in the figure:

• Event 1: The user enters a local telephone number for the service provider. The modem dials this number. It is relayed through the local exchange carrier (LEC, not shown here) to the called party: a router serving at the service provider.

  Figure 7-1. An example of the handshakes ...