Voice over IP (VoIP) has become an important factor in network
communications, promising lower operational costs, greater
flexibility and a variety of enhanced applications. To help you
understand VoIP networks,
Voice over IP Fundamentals
explains how a basic IP telephony infrastructure is built and works
today, major concepts concerning voice and data networking and
transmission of voice over data networks. You'll learn how voice is
signaled through legacy telephone networks, how IP signaling
protocols are used to interoperate with current telephony systems
and how to ensure good voice quality using quality of service
(QoS).
Even though Voice over IP Fundamentals is written for
anyone seeking to understand how to use IP to transport voice, its
target audience comprises both voice and data networking
professionals. In the past, professionals working in voice and data
networking did not have to understand each other's roles. However,
in this world of time-division multiplexing (TDM) and IP
convergence, it is important to understand how these technologies
work together. Voice over IP Fundamentals explains all the
details so that voice experts can understand data networking and
data experts can understand voice networking.
The second edition of this best-selling book includes new
chapters on the importance of billing and mediation in a VoIP
network, security and the common types of threats inherent when
packet voice environments, public switched telephone networks
(PSTN) and VoIP interoperate. It also explains enterprise and
service-provider applications and services.
Click here for the
chapter download or
to purchase the book.
In this chapter:
Billing and mediation services are important in Voice over IP
(VoIP). They are key factors in helping a service provider or an
enterprise vendor understand financial aspects -- such as Return on
Investment (ROI) -- when migrating from time-division multiplexing
(TDM)-based network to VoIP. The public switched telephone network
(PSTN) world offers a simpler billing structure for calls made over
the network because the originator and the destination points are
static and tied to a physical location. It also expects voice
traffic and data traffic to be billed in different ways. VoIP
changes this paradigm and allows the endpoints to move. The voice
and data traffic are all packets that are transported from one
location to another over the network. This raises some issues and
requires protocol definitions on whom to bill, where to bill and
what to bill. Chapter nine of Voice over IP Fundamentals
discusses what network administrators need to know about combining
voice and data while maintaining organization and concise
records.
Read more about VoIP billing and mediation
services in this PDF.
Excerpted from
Voice over IP Fundamentals, Second Edition, July
2006 by Jonathan Davidson, James Peters, Manoj Bhatia,
Satish Kalidindi, Sudipto Mukherjee. ISBN: 1-587-0525-71.
Copyright © 2006, Cisco Press. All rights reserved.