CHAPTER 1: INTRODUCTION
Everything old is new again
Existing information-security technologies and processes often resemble historical methods to provide confidentiality, integrity and availability.
In the Middle Ages, the use of castle walls, gates, and drawbridges allowed for certain people to come or go only as desired by those in charge. Today, a firewall ensures that data can only enter or leave specific network ports as defined by configured filtering-rule sets. Similarly, Julius Caesar utilised primitive cryptography thousands of years ago to transmit instructions and guidance to his Roman army. While cryptography still has its place among military engagements, it also helps us protect everything from our private photos to credit card ...