The voice services maze

Introduction

Voice is the one telecommunications service which everyone understands. Making voice calls is what we all use the telecoms networks for, and voice calls are still the mainstay of telco revenues.

But underneath this apparent simplicity there is a virtual maze of different routes for delivering voice services. The maze is created because there is a range of choices available to would-be providers of voice services at each level in the 'service stack'. The Figure shows a simplified representation of the choices, splitting the stack into just three layers with the main choices at each level. Different voice services involve combining different choices from each of these layers. The aim of this document is to identify and distinguish the main alternative voice services which are emerging from this plethora of choice.