SIP- Understanding the Session Initiation Protocol Description:

SIP: Understanding the Session Initiation Protocol review:
2 stars (OK but could be much better written) - The information contains in the book makes it a pretty good primer on SIP. The organization of the book and its content is very good. The language and ways in which the author explains certain things are confusing. I think the author should be able to do a much better job in explaining things. I often find myself having to re-read certain explainations twice and much carefully when I feel I shouldn't have to -- the topics are not complicated but not well explained. Someone like Doug Comer or Richard Stevens would probably be able to make it a much easier read.
4 stars (Costly, but a great introduction to SIP) - Really enjoyed this book - easy to read, and the examples emphasized the points he was trying to make. The only negative is the cost of the book ... I got mine from the library, and was shocked to see how much this was selling for. After you understand SIP, this would be a decent reference book, but not the best.
3 stars (Just an introduction to the SIP RFC) - This book simply summarizes some of the SIP RFC into more user-friendly english. It consists mostly of lists of SIP headers and error codes, lifted from the RFC. There is no sample code or discussion of SIP applications or architecture. Of course, the RFC is pretty hefty, so this book has been a useful introduction. I still use the RFC as my real reference, though, because there are some minor discrepancies between the book and the RFC, such as some error code names.