Rating: 

Little explanation is given in this guide on the theory of packet filtering and network address translation (NAT), and the examples, as is so typical of a lot of Linux documentation, make too many assumptions about the reader's knowledge. In particular, the NAT section is woefully inadequate -- I can glean more information about NAT from the ipfilters man page.

I was also disappointed in the typesetting of this guide. The font is too small and the font weight produces, in my opinion, a poor contrast between characters and paper. I struggled trying to read this guide in anything other than high light levels and concluded that I had wasted my money. I'll keep it here in my library (returning it would cost almost as much as it's worth) but it will probably gather a lot of dust.