The Book of PF (No Starch Press, December 2007, 184 pp, ISBN 9781593271657 I've been using IPTables under Linux for quite some time now but with the poorly implemented firewall tool under Mac OSx Leopard, this book by NoStarch press has arrived in the proverbial nick to time. It's my best guess that Apple tore away a goodly number of programmers off Leopard to make sure that Steve Job's promise for the iPhone w The Book of PF (No Starch Press, December 2007, 184 pp, ISBN 9781593271657I’ve been using IPTables under Linux for quite some time now but with the poorly implemented firewall tool under Mac OSx Leopard, this book by NoStarch press has arrived in the proverbial nick to time. It’s my best guess that Apple tore away a goodly number of programmers off Leopard to make sure that Steve Job’s promise for the iPhone was fulfilled. The downside is that Leopard had a few missing pieces, one of which was a polished interface for the built in firewall. So while this book isn’t precisely for the poor Leopard users, I don’t see why quite a bit won’t work anyway due to OSx’s BSD roots. With Mr. Hansteen paying close attention to important topics like: state inspection, SPAM, black/grey listing, and many others; this must have reference for BSD users can go a long way to helping you fine tune the who/what/where/when/how of access control on your BSD box.*NOTE: NoStarch Press is a rare beast in that almost all of their new books are also available in PDF format. Deep discounts are available if you purchase both the paper and electronic version at the same time, but you can always get either paper or PDF off their website. The truly FOSS thing about NoStarch is that they’re trusting their readers in that they only really watermark the PDF version with the owner’s information. No other DRM is involved….I for one will be voting with my dollars and I sincerely hope you folks out there do the same for your reference collection. Technology Industry