The best possible defense is to regularly test your network to reveal the vulnerabilities and close the holes. The book includes both common and custom usages, scanning methods, and reporting routines of each of the most popular software systems. It also includes how to install and install software on your computer to prevent hackers from getting into your network. The book is available on Amazon.com and Google.com for more information about how to use the book.com/secure.com to test your systems and your network security.”]
Source: https://www.amazon.co.uk/exec/obidos/ASIN/0471229466/helpnetsecuri-21