NOTE FROM CLEMENT:

Nmap is really the mother of all port scanners.  It can help you on the defensive side to identify ports that are currently open, new IP's that have just shown up in your production environment, ports that are either added, deleted, or modified on your hosts.  Find what is happening to your servers as soon as changes manifest themselves.  This is really a great tool for regular scanning and discovery of port and services that should or should not be on your servers.  This book is written by Fyodor the author of Nmap, there is nobody else that knows Nmap better then Fyodor.  I highly recommend it to all.  See announcement below from Fyodor:

Nmap Hackers:

After promising you a book on Nmap for years, I'm delighted to finally announce the release of Nmap Network Scanning! It contains everything I've learned about network scanning from more than a decade of Nmap development, plus some bad jokes and (over Time Warner's written objections) pictures of Trinity hacking the Matrix :) . Here is the abstract:

Nmap Network Scanning is the official guide to the Nmap Security Scanner, a free and open source utility used by millions of people for network discovery, administration, and security auditing. From explaining port scanning basics for novices to detailing low-level packet crafting methods used by advanced hackers, this book by Nmap's original author suits all levels of security and networking professionals. The reference guide documents every Nmap feature and option, while the remainder demonstrates how to apply them to quickly solve real-world tasks. Examples and diagrams show actual communication on the wire. Topics include subverting firewalls and intrusion detection systems, optimizing Nmap performance, and automating common networking tasks with the Nmap Scripting Engine.

The planned release date was January 1, but Amazon beat the deadline and is now shipping in time for Christmas! Imagine your loved one's surprise when she (or he) finds nearly 500 pages of port scanning
bliss in her stocking!

You can find reviews, sample chapters, and a detailed summary at:

http://nmap.org/book/

Or you can pick the book up at Amazon for $33.71:

Nmap Network Scanning: The Official Nmap Project Guide to Network Discovery and Security Scanning

It is available on the International Amazon sites too, as well as other online retailers. Your local book store probably doesn't have it yet, but can likely order it for you.

About half of the content is available free online at http://nmap.org/book/toc.html . Chapters exclusive to the print edition include "Detecting and Subverting Firewalls and Intrusion Detection Systems", "Optimizing Nmap Performance", "Port Scanning Techniques and Algorithms", "Host Discovery (Ping Scanning)", and more.

If you enjoy the book, please help spread the word! While my previous books were published by Addison-Wesley and Syngress, this one was self-published. While that allowed me to post half the book online before it was even released, it also means I lose the marketing budget and clout of a major publisher. So if you like the book, please post a review to your blog/site/Amazon or tell your friends about it!

Apparently there was some pent-up demand for the book, as it is currently the 11th best-selling computer book on Amazon. Maybe it will be even higher by the time you read this:

http://www.amazon.com/gp/bestsellers/books/5/ref=pd_zg_hrsr_b_1_2&tag=secbks-20

I'd like to thank the many people who helped make this book possible by reviewing drafts, contributing stories, brainstorming ideas, etc. In particular, I'd like to thank David Fifield, Raven Alder, Matt Baxter, Saurabh Bhasin, Mark Brewis, Ellen Colombo, Patrick Donnelly, Brandon Enright, Brian Hatch, Loren Heal, Lee "MadHat" Heath, Dan Henage, Tor Houghton, Doug Hoyte, Marius Huse Jacobsen, Kris
Katterjohn, Eric Krosnes, Vlad Alexa Mancini, Michael Naef, Bill Pollock, David Pybus, Tyler Reguly, Chuck Sterling, Anders Thulin, Bennett Todd, Diman Todorov, and Catherine Tornabene!

And most importantly, I want to wish you all happy holidays!

Cheers,

Fyodor

Get your copy now:

Nmap Network Scanning: The Official Nmap Project Guide to Network Discovery and Security Scanning