Book details of 'IP Telephony: Packet-Based Multimedia Communications Systems'

Title	IP Telephony: Packet-Based Multimedia Communications Systems
Author(s)	Olivier Hersent, David Gurle, Jean-Pierre Petit
ISBN	0201619105
Language	English
Published	December 1999
Publisher	Addison-Wesley Pub Co

---

Back to shelf Computer networks
Amazon.com info for IP Telephony: Packet-Based Multimedia Communications Systems

Score:

Vote for this book

The Virtual Bookcase Reviews of 'IP Telephony: Packet-Based Multimedia Communications Systems':

Reviewer amazon.com wrote:
Voice communications over the Internet--particularly the direct, sender-initiated kind--haven't yet taken off, but lots of smart people say Internet telephony is going to be huge before long. In IP Telephony, three experts on getting voice signals from here to there, intact, via Internet Protocol (IP) networks hold forth on the state of the art. Like Voice over IP (VoIP) itself, their discussion is largely academic. Rather than show how to implement VoIP with any of the tools available for that purpose, the authors put most of their effort into elaborating on the specifications that govern (or at least aspire to govern) Internet telephony. It's an approach that IP telephony software developers will appreciate. The denseness of the prose in this book is offset by high-quality conceptual diagrams. In particular, the timelines do a great job of explaining signal sequences, and flow charts communicate logical processes effectively. In the sections on the mechanics of converting sounds into bits (which are loaded with equations and other descriptions of algorithms), the discussion of the phenomena that cause signals to degrade is especially clear. As a whole, IP Telephony is a good description of a developing technology. --David Wall Topics covered: The appeal of Internet telephony, and the progress to date on standards for implementing it. The emerging H.323 protocol suite gets lots of attention, as does the Session Initiation Protocol (SIP) and the Media Gateway Controller Protocol (MGCP). Coverage also includes algorithms for converting audio information into digital data band back again, as well as quality-of-service (QoS) and conferencing with multicasting.
Reviewer Rob Slade wrote:
The preface does a rather heavy-handed sell on IP telephony, without really backing up any claims. It doesn't really define a specific audience, although the set of people who are listed as possibly being interested is a fairly limited one. The preface also expects a strong familiarity with ISDN (Integrated Services Digital Network) and TCP/IP networking. I'm not sure that I understand the requirement for ISDN, but a strong technical background is a must, if you are going to tackle this book. The authors don't appear to have made much attempt to ensure that it is readable, or even lucid. The text resembles nothing so much as a mass of technical trivia, only nominally organized. Ironically, despite the heavy technical content, there does not seem to be enough detail in the work to ensure that even dedicated readers will be able to produce some kind of implementation. Section one supposedly talks about application layer IP telephony protocols, although much of the material appears to be more appropriate to the session layer. Chapter one is huge, touching on the H.323 standard, RTP (Real-time Transfer Protocol), security, codecs, and an extensive H.323 session walk-through. The alphabet soup is thick, and not always defined. RAS (Registration, Application, Status, in this case) is not expanded at any point prior to page six, where it is used for the first time and noted as being defined "above," although it is based on H.225.0 which gets mentioned "above." H.323 is a complex standard which is somewhat non-standard, but the lack of any logical progression in the writing is not going to help the reader follow the material. The Session Initiation Protocol (SIP), in chapter two, appears to be something of an Internet-based contender to the ITU's (International Telecommunications Union) H.323. The Media Gateway Control Protocol (MGCP) seems to be a broader technology in some competition and cooperation with both, in chapter three. Section two looks at voice technology. Chapter four touches on a number of topics related to voice quality, but mostly concentrates on delay. Lots of math, tables, and flowcharts fail to explain much about voice coding in chapter five, which primarily seems to be a historical progression of standards. Section three discusses the network. Chapter six talks about quality of service (again emphasizing delay). Network dimensioning, in chapter seven, provides lots of math for figuring out the minimum bandwidth you need. IP multicast routing is the topic of chapter eight. Ultimately, this book might be most useful as a pointer to other sources of information, such as the standards themselves. copyright Robert M. Slade, 2000
Add my review for IP Telephony: Packet-Based Multimedia Communications Systems

Book description:

"This book embraces all of the fields that the VoIP professional needs to be aware of in a clear and organized way... I recommend this book to all VoIP engineers, analysts, and IT managers who really want to know what they are talking about on the net, enjoy!" -Jeff Pulver, founder of the VON (Voice On the Net) coalition, and the founder and president of pulver.com Internet Telephony is now one of the most important and fastest growing technologies on the Internet, providing a viable technical and economical alternative to current telecommunication networks. Network providers and major companies are thus investigating how this emerging technology can be implemented, and at what cost and savings, in their organizations. This book provides a comprehensive practical overview of the technology behind Internet Telephony, giving essential information to IT professionals who need to understand the background and explore the issues involved in migrating the existing telephony infrastructure to an IP based real time communication service. Assuming a working knowledge of IP and ISDN networking, it addresses the technical aspects of real-time applications over IP, with an in-depth coverage of voice and video applications and protocols. Drawing on their extensive research and practical development experience in VoIP from its earliest stages, the authors give you access to all the relevant standards and cutting-edge techniques in a single resource. IP Telephony is organized into three clearly structured sections, focusing on protocols, voice technology and networks with a step-by-step approach. The protocols section sets IP telephony in context and then covers H.323, SIP and MGCP in detail, examining in turn their pros and cons, and using examples of particular cases and scenarios. The voice technology section describes voice quality, including the ETSI TIPHON approach, and voice coding, with summary comments on the applicability to VoIP telephone gateways. The final section on networks addresses Quality of Service (QoS) issues, explores dimensioning a VoIP network, and introduces Multicast routing, including a perspective on security and MBONE applications. Features: *detailed, up-to-date coverage of voice and video applications and emerging protocol standards:H.323, SIP, MGCP *practical strategies on how to plan and dimension a VoIP network *key points to look for in choosing a VoIP product & how to avoid common pitfalls in implementation *examples and illustrations of standards and techniques including feedback information on issues discussed at standards meetings *details of QoS issues, Intserv (RSVP), DiffServ, RTP, SDF, companion standards, multimedia coding standards and coding algorithms<