Chapter 4. Voice Over Ethernet
This chapter introduces the technologies necessary to carry voice over wireline packet networks. The first half of the chapter is a basic review of the concepts within packet networks, including IP and Ethernet. The second half takes a look directly at voice over these networking technologies.
4.1. The IP-Based Voice Network
The previous chapters explored the basics of how calls are set up and voice is carried over packet-based IP networks. However, the details about what makes the IP network itself work have not yet been addressed.
Voice started out on analog phone lines. Each pair of copper wires was dedicated to one specific phone, and to nothing else. This notion of a dedicated circuit has its advantages. ...