Daniel J. Barrett has been immersed in Internet technology since 1985. Currently working as a software engineer, Dan has also been a heavy metal singer, Unix system administrator, university lecturer, web designer, and humorist. He is the author of O'Reilly's Linux Pocket Guide, and is the coauthor of Linux Security Cookbook, and the first edition of SSH, The Secure Shell: The Definitive Guide. He also writes monthly columns for Compute! and Keyboard Magazine, and articles for the O'Reilly Network.