ABSTRACT
For the first 40 years or so of the computer era, the question of security was on the one hand widely ignored, and on the other hand relatively simple to address. The reasons, of course, were that far fewer people had access to computing, and also the environment for the computer user was essentially a corporate or university mainframe computer that had no connectivity with other machines that were outside of that corporate environment. However, beginning in the early 1980s, with the rapid expansion of computing power available to larger and larger segments of the population, along with the emergence of the Internet, public awareness grew with a number of attacks on large numbers of computer systems. From the Morris Internet worm of 1988 through the devastating attacks of recent years, the challenge of defending large networks of computer systems has led to vastly increased attention on what we now call “cybersecurity.” In this chapter, we will look at this history, and also some fundamental approaches to defending our computing environments based on the principles of secrecy, accuracy, and availability. And we will analyze the dangers in these environments by identifying vulnerabilities, threats, and countermeasures.
