UNIX Computing Security/Introduction

The only secure computer is one that's unplugged, locked in a safe, and buried 20 feet under the ground in a secret location... and I'm not even too sure about that one. —Dennis Hughes, FBI

UNIX is a computer operating system that was first developed during the 1960s and 1970s at AT&T Bell Labs. It was originally conceived as an academic operating system, particularly at the university level, and hence security was not a top priority of the design. Since then, however, UNIX computing systems have been made more widely available and have become an essential part of networking and internet infrastructure. The increased level of access and the need for data security have driven improvements to UNIX security features. The evolution of UNIX security features continues to this day, with an increasingly urgent need for preventing inappropriate access to systems and their data.

This book is intended for an audience that has at least a basic familiarity with the UNIX operating system, including common shell commands, the directory structure, and file manipulation. The primary focus will be for the System Administrator of a UNIX system. That is the operator who is responsible for configuring and maintaining a functioning system, as well as troubleshooting system failures, controlling user access to the system, and so forth.

As there are multiple variations of the UNIX operating system made available by various computing vendors, not to mention related operating systems such as Linux, this book will cover topics common to most of the UNIX releases. Features specific to a particular vendor's release will be noted accordingly.