I bought this book in order to understand and sort out the problems with the DNS setup of a large customer running multiple Unix systems. While it was a one-off purchase for a single job rather than part of any ongoing task I feel it was money very well spent. Whilst readable it is clearly a solid technical textbook aimed at people who do this for a living rather than a popular guide. For someone who just wants to learn about how the Internet works out of curiosity it would be pointless to buy this book. Ideally you need a fair knowledge of such things as Unix and TCP/IP to get the best out of this book, but if like me you do this to pay the mortgage and put food in front of the children, then this book is a must have for the low down on BIND and DNS.