Hacking Multifactor Authentication

3Types of Authentication

Humans have been performing authentication using one form or another for millennia. Authentication doesn't have to be digital. There are hundreds of different authentication solutions, human and digital, one-factor and multifactor, which can be divided between a dozen categories. This chapter will cover the major authentication solution types, along with advantages and disadvantages of each. It will also describe cryptography and how it applies to authentication. This is the longest chapter of this book because it takes a few inches to cover each type—and there are a lot of types. Still, I hope you find it an interesting summarization worth your time.

Personal Recognition

The most common form of authentication is personal recognition: we recognize one another. When spouses wake up together in the morning, as long as they recognize each other, no one screams. Most of us are allowed to walk into our day jobs, work all day, and get paychecks because everyone around us, from our boss to our coworkers, physically recognizes us. In the very early days of the computer, when it was a single, huge, supercomputer that took up an entire room, the computer technicians recognized one another. Early on there was no remote networking or connections. If you wanted to work on the computer, you had to show up in the computer room.

Personal recognition even works when we don't know one another. If I order a pizza from Dominos and a delivery person shows up in a Dominos ...