Introduction to Cybersecurity

This book provides an introduction to the basic ideas involved in cybersecurity, whose principal aim is protection of IT systems against unwanted behaviour mediated by the networks which connect them. Due to the widespread use of the Internet in modern society for activities ranging from social networking and entertainment to distribution of utilities and public administration, failures of cybersecurity can threaten almost all aspects of life today.The book deals with cybersecurity as an interdiscplinary challenge. An IT system consists of hardware, software and human users, all of which can contribute to the success or failure of efforts to maintain cybersecurity. The book deals first with basic questions such as: How can humans be exploited to breach cybersecurity? How can we analyse the risk of cybersecurity failures? How can cryptography be applied to achieve suitable security aims? How do networks such as the Internet and the telephone network work?It then goes on to look at some more specific areas of importance for IT systems: How is security achieved in the networks themselves? How does the operating system in modern computers support security? What risks often appear in software products, and how can they be avoided? How does one deal with attacks, if -- in spite of all precautions -- they actually succeed? What laws or ethical principles apply to various types of activity in cyberspace?Each chapter contains exercises of various types, to stimulate both the reader's theoretical understanding of the topic of the chapter, and to encourage the reader to perform practical experimentation.The text is intended for readers who do not yet have any in-depth knowledge of computer systems, such as CS/EE undergraduates or personnel in non-IT areas, who need to understand how cybersecurity failures arise and can be countered. Mathematical requirements have been kept to a minimum and no knowledge of programming is needed.