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Rating: 
Summary: Excellent book even in english
Review: Book includes important information on VoIP protocols, voice quality, SS7 and how to test. The ITU-T and RFCs are summarized,which we can understand easily. Helpful for our troubleshooting about VoIP network. Excellent book even in english.
Rating:
Summary: Excellent book even in english
Review: Book includes important information on VoIP protocols, voice quality, SS7 and how to test. The ITU-T and RFCs are summarized,which we can understand easily. Helpful for our troubleshooting about VoIP network. Excellent book even in english.
Rating: 
Summary: Author's comments on IP Telephony
Review: Dear reader,In the last few years we have made tremendous strides towards achieving telephone service integration with video and data applications. Early multiservice offerings and pilot programs of integrated multimedia applications have paved the road towards a speedy renovation of the telephone network, beginning at the access. The complexities involved in making this promise real are enormous and the hurdles we have overcome to this point, and still need to overcome as we continue to learn, are many. If you are an engineer like myself working close to this problem, you can certainly relate to the amount of technical information that needs to be absorbed so one can understand the manner telephony will be handled in the new world. When I started writing this text and took a step back, I was overwhelmed by the breadth and depth of the topic. Voice over IP spans many technical subjects, beginning with signaling to make a call. Carrying the media streams - voice, video, data - has its own complications too, particularly if one contemplates creating a single network to carry all types of traffic. I have been through a few go-arounds of this type of effort in my career, and the underlying technical constraints only get tougher as bandwidth and topologies scale to new heights. Supporting existing applications in a transparent manner - e.g. facsimile - is also mandatory for the consumer acceptance of the new technology. And let's not forget when all is said and designed, we need to test it in a manner that represents real conditions before a service that meets performance requirements can be deployed and brought to our homes and businesses. The book covers three of the major signaling protocols for VoIP - H.323, SIP and MGCP - as well as interactions between them and SS7 signaling for the completion of a call across multiple domains using different signaling methods. We discuss issues in media encoding and transport, as well as voice quality testing using the Hewlett-Packard / Agilent Technologies Voice Quality Tester instrument, which employs the ITU-T PSQM algorithm. We offer an explanation of the algorithm and a case study of mapping network impairments to measurable impact on voice quality. The use of instrumentation in constructing test scenarios is also discussed in the case study. Integrating simple voice and voiceband, i.e. fax, applications is not simple. A section is dedicated to fax support using the T.30, T.37, T.38 protocols, and up to V.34 modulation. Wherever possible, the technical issues of supporting telephony applications are discussed over generic packet networks. I have been fortunate to have the support of Hewlett-Packard / Agilent Technologies in producing this text and review from a world renowned expert in facsimile, Mr. Mike Gray, the founder of Telegra. I hope you enjoy the book. Bill Douskalis,
Rating:
Summary: The best so far....
Review: Excellent level of detail, well written and clearely illustrated. A must for anyone interested in signaling and protocol interworking.
Rating: 
Summary: Waste of time and money
Review: Pitiful attempt to push Agilent test equipment, by giving itself the appearance of a textbook. Doesn't go beyond the basics. No mentioning of perceptual voice quality problems. Don't waste you time and money on this book. I am going to return this one... The CDROM contains nothing but Agilent datasheets...geez..
Rating: 
Summary: Excellent overview with some good meat in it
Review: The author does an excellent job at covering a lot of ground, and balances high-level description with technical detail. It gives a good lay of the land in this topic, discusses the problems, details the protocols, and overall gives you a good footing when it's time to go read the ITU specs and RFC's. Highly recommended.
Rating:
Summary: Excellent overview with some good meat in it
Review: The author does an excellent job at covering a lot of ground, and balances high-level description with technical detail. It gives a good lay of the land in this topic, discusses the problems, details the protocols, and overall gives you a good footing when it's time to go read the ITU specs and RFC's. Highly recommended.
Rating:
Summary: A friendly explanation of a complex technology
Review: This book is a very useful resource helping you to retrieve a lot of informations with no waste of time. A very clear exposition leads the reader to uncover this exciting cutting edge technology.
Rating:
Summary: Obviously I highly recommend it (our department has two)
Review: This book is an excellent resource for the Telecommunications professional who is trying to deploy VoIP. It covers most of the major signaling protocols you'll find in VoIP based networks. It also covers how voice traffic is actually carried across IP networks (RTP and RTCP). It details network designs and network design concerns, as well as providing a case study on how to test these designs. It finishes with a thorough explanation of Fax and Fax over Packet networks. The book comes with six major sections: Signaling, Media Transport, Call Control, Voice Quality, Case Study, Fax. While I cannot list all of the details covered in each section, I did highlight some of those I found useful. I'm sure I will have left something out and later wished I had added it; but this just shows the breadth and depth of the book. Under the Signaling section, the author reviews in some detail SGCP, MGCP, and NCS. H.323 is covered very well (includes normal and FastConnect procedures). SIP is also covered in great detail. The use of SDP for each of the above protocols is discussed as well. Under the Media Transport section, RTP and RTCP are covered in great detail. RSVP and implementation concerns are discussed. Finally, a glimpse into topics that reduce header bandwidth for use in low bandwidth applications is also discussed: AAL2, IP Header compression. The Call Control section does a good job of blending TDM networking (SS7) with VoIP networking for the basis of call setup and application interaction. This section includes call flows (a good picture is worth a thousand words) as well as descriptive text. This section also reviews SS7 for the reader to ensure agreement on all of the important topics. The Voice Quality section is the first book that really delves into PSQM. It shows how to use this technique. This section also spends a good deal of time with real network measurements utilizing HP test equipment. I'm convinced PSQM will be used by network engineers in determining their network quality. The Case Study section helps the reader through how to test a VoIP network. It also shows different ways of measuring the same thing (very helpful, since your network may or may not have a given link layer). Finally, the last section on fax is very well written. It covers all of the major protocols (T.30, T.37, T.38) and even delves into obscure, but important topics like what a fax preamble is, when phase reversal occurs, etc. No author can write one book for all readers. Likewise, a quality review doesn't just look at the positive. This book has a few areas that the reader may want more information on, and they will have to look elsewhere (or wait for the second edition?). For example: in the signaling plane, IPDC is not discussed. This is not that big a deal since IPDC handles call control much like SGCP and MGCP, but IPDC certainly brings some new wrinkles into the picture. TALI is also not covered in the signaling plane, but will play a major role in SS7 message transfer for a lot of networks. In the bearer plane, I would like to have seen a little more explanation around the Layer 2 overhead. PPP, AAL5, even FR add noticeable overhead on top of VoIP. While this topic was discussed (pp. 92-95), it is assumed the reader is knowledgeable enough in this area to be able to calculate their implementation's use of bandwidth in the bearer plane. Bearer Latency is also discussed, but again, only 2 pages here, and no real way to apply this to the reader's specific problem area. Overall a very high quality book. While it may not be written for the novice VoIP engineer, it certainly covers almost all of the major topics in enough detail to be useful for almost anyone else in the VoIP arena. Obviously I highly recommend it (our department has two). Shannon
Rating:
Summary: Obviously I highly recommend it (our department has two)
Review: This book is an excellent resource for the Telecommunications professional who is trying to deploy VoIP. It covers most of the major signaling protocols you'll find in VoIP based networks. It also covers how voice traffic is actually carried across IP networks (RTP and RTCP). It details network designs and network design concerns, as well as providing a case study on how to test these designs. It finishes with a thorough explanation of Fax and Fax over Packet networks. The book comes with six major sections: Signaling, Media Transport, Call Control, Voice Quality, Case Study, Fax. While I cannot list all of the details covered in each section, I did highlight some of those I found useful. I'm sure I will have left something out and later wished I had added it; but this just shows the breadth and depth of the book. Under the Signaling section, the author reviews in some detail SGCP, MGCP, and NCS. H.323 is covered very well (includes normal and FastConnect procedures). SIP is also covered in great detail. The use of SDP for each of the above protocols is discussed as well. Under the Media Transport section, RTP and RTCP are covered in great detail. RSVP and implementation concerns are discussed. Finally, a glimpse into topics that reduce header bandwidth for use in low bandwidth applications is also discussed: AAL2, IP Header compression. The Call Control section does a good job of blending TDM networking (SS7) with VoIP networking for the basis of call setup and application interaction. This section includes call flows (a good picture is worth a thousand words) as well as descriptive text. This section also reviews SS7 for the reader to ensure agreement on all of the important topics. The Voice Quality section is the first book that really delves into PSQM. It shows how to use this technique. This section also spends a good deal of time with real network measurements utilizing HP test equipment. I'm convinced PSQM will be used by network engineers in determining their network quality. The Case Study section helps the reader through how to test a VoIP network. It also shows different ways of measuring the same thing (very helpful, since your network may or may not have a given link layer). Finally, the last section on fax is very well written. It covers all of the major protocols (T.30, T.37, T.38) and even delves into obscure, but important topics like what a fax preamble is, when phase reversal occurs, etc. No author can write one book for all readers. Likewise, a quality review doesn't just look at the positive. This book has a few areas that the reader may want more information on, and they will have to look elsewhere (or wait for the second edition?). For example: in the signaling plane, IPDC is not discussed. This is not that big a deal since IPDC handles call control much like SGCP and MGCP, but IPDC certainly brings some new wrinkles into the picture. TALI is also not covered in the signaling plane, but will play a major role in SS7 message transfer for a lot of networks. In the bearer plane, I would like to have seen a little more explanation around the Layer 2 overhead. PPP, AAL5, even FR add noticeable overhead on top of VoIP. While this topic was discussed (pp. 92-95), it is assumed the reader is knowledgeable enough in this area to be able to calculate their implementation's use of bandwidth in the bearer plane. Bearer Latency is also discussed, but again, only 2 pages here, and no real way to apply this to the reader's specific problem area. Overall a very high quality book. While it may not be written for the novice VoIP engineer, it certainly covers almost all of the major topics in enough detail to be useful for almost anyone else in the VoIP arena. Obviously I highly recommend it (our department has two). Shannon
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