Customer Reviews

IP Telephony

5 star:		(3)
4 star:		(0)
3 star:		(1)
2 star:		(2)
1 star:		(1)

 

 

This book is a very good overview of IP Telephony and other related technologies such as multicasting network and quality over service. I am a software developer and not the telecommunication engineer, and surprsingly the book helps me a lot in understanding IP Telephony as a software developer.

First part of the book explains three standards H.323 of ITU, SIP of IETF, and MGCP. Second part explains Voice Technology, and finally , the third part explains Network part. They are explained quite clearly and the writers not only know what they are saying, but also they know how to say it right.

Although I do give 5 stars , I prefer to give this book 4.5 stars since I don't think one can undestand the book if they have not read the H.323 specification before, have no idea about multicasting, ISDN, SS7, RTP/RTCP. So, if you have no idea about all of the issues..., I don't think this book will help you. Read H.323 specification, IP multicasting, RTP/RTCP (or other multimedia and networking), QoS, before and then read this book. It does not mean that you have to understand all the stuffs, just a little knowledge for dummies for each is enough.

This book is disappointing. However, to be fair, all the books I read so far on IP-Telephony are disappointing. The problem is that this is a new and fast evolving area, it is hard to understand all facets of the technology to write a comprehensible and easily-understandable book. People who are in-the-know are probably working on very specific projects on IP-Telephony in some start-ups (meaning that they don't have time nor energy to write a book and don't know the entire field well enough to write anyway). That left people who are mostly "pretenders."

Take this book for example, it is so badly written that I doubt anyone without prior exposure to IP-Telephony can understand the material. There are so many acronyms used without proper definition, so many graphs used without meaningful captions or explanation in the text. Many descriptions in the text were copied straightly from standard documents (which are themselves not readable). And it is quite obvious that the authors do not know many of the subjects that they talk about - basically, they just "wing" it. The authors lack a global picture of how different standards relate to each other and interoperate. For example, the dscription of MGCP is so confusing it is obvious that the authors have no idea how it relates to H.323, SIP. etc.

Avoid this book. Sorry I do not have any recommendation to a good book.

This book has the best description of RTP, H.323, SIP and MGCP I have seen yet. It's sufficiently technical that it answers what a programmer needs, yet it's at a level higher that the actual specs so you can quickly arrive at a high-level understanding.

I personally found it on the bookshelf at a local store and thought it worth the risk of a purchase... and I find that my money was very well spent indeed. I highly recommend it to anyone who is not already an expert Internet Telephony.

In my opinion this is a very serious descriptive book, for Voice over IP standards. I work in an chilean operator, and the book clarified me regarding the state-of-the-art of these technologies, and give me a good theoretical background.

Currently there are many confusion regarding this field, because the different proposed standards. This book cover H.323, SIP and MGCP. Although some of them were not completely published a the writing-time, the protocols are very well explained (including some message exchange between devices).

There are some chapters over Voice Coding and Quality of Service, which will be very interesting for any engineer who is planning a real deployment. Chapter 7 is for Network Planning (very useful).

This is a technical book, recommendable for engineers, with a good networking knowledge. Until now, is the most serious book I have found regarding this topic.

For me (non-engineer, support staff) this book was a complete waste of time. Since it was highly recommended to me by an engineer who is very knowledgeable in IP telephony, I assume that for others it can be useful. I suspect those others either should be very experienced engineers or should have PHD's in both mathmatics and IP telephony. It most definitely is not an introductory-level book.

Despite the title, a significant portion of this book is dedicated to topics (such as QoS and multicast) that are not really VOIP-specific. While it's true that VOIP implementations may make use of them, that doesn't mean that they should be used to pad out the back half of the book. (Why not discuss IP packet headers and IP routing protocols while you're at it?) There are plenty (maybe even too many) books out there on IP multicast already, and I would have preferred for this book to be more focused on VOIP-specific topics.

Also, the coverage of protocols reads more like a review than a tutorial -- not a "Teach Yourself VOIP" book by any stretch of the imagination. If you're not familiar with H.323/SIP/MGCP already, this is probably not the place to start. The sections on voice coders and network dimensioning also read like a doctoral dissertation or an IEEE journal article.

Still, not a bad book, but a little less generic technology chapters and more on protocols, voice quality, and implementation issues would have helped it live up to its title.

what actually is dealt on trunk reource management of ip telephony. what numbering plan is used here