Now that we have laid the groundwork regarding wireless LANs and voice over IP technology, we can look at how these come together in a voice over wireless LAN configuration. This is the first of several chapters that will deal specifically with WLAN voice. In this first chapter we will look at the major hardware elements that go into a WLAN voice network, how they are configured, and how they interface with the wired telephone system. In the following chapters we will describe the technical requirements, design, planning, and network management functions to be addressed. We will also investigate the potential of Fixed Mobile Convergence, the idea of integrating WLAN voice with cellular technology to provide an all-encompassing mobile voice capability.

WLAN voice began in earnest in 2003, when companies like SpectraLink (now part of Polycom), Symbol Technologies (now part of Motorola), Vocera, and Cisco introduced WLAN voice handsets and the equipment to support them. A number of enterprises, particularly in health care and materials handling, deployed small-scale VoWLAN networks. Those installations were small-scale by choice as customers found that the initial crop of Wi-Fi products lacked many of the important features that would allow these networks to provide the scale, security, and other features required for a large-scale deployment. Handsets with those required features arrived on the market in 2007.

In this chapter, we will look at the architecture, infrastructure, and device requirements for a WLAN voice solution. We will begin with the overall architecture choices and then review...