IN THE DAYS BEFORE THE INTERNET, MOST HACKERS COMMUNICATED THROUGH THE TELEPHONE SYSTEM. Instead of using the Internet, people crowded into online services with odd names like The Source and GEnie, and not so odd names like CompuServe and America Online. Instead of setting up web sites, people set up electronic bulletin board systems (BBS). Most importantly, instead of linking computers together through high speed cable, DSL, or satellite Internet connections, people had to connect to one another through the much slower telephone lines.
The problem wasn't necessarily the slowness of the telephone system. The problem was that the cost of multiple long distance phone calls quickly added up. To avoid paying the least amount of money to the telephone company as possible, many people simply figured out various ways to manipulate the telephone company's computers to remove charges from their bills or grant themselves free telephone service so they could make as many long distance phone calls as they wanted.
These early hackers were called phone phreaks, and their methods were known as phone phreaking. On the noblest level, phone phreaking was about exploring, experimenting, and learning as much as you could about the telephone system out of sheer curiosity. On a more malicious level, phone phreaking meant making free phone calls at somebody else's expense, denying phone service to valid customers, or even wrecking telephone company equipment.
Unlike computer hacking, which can often be practiced in isolation on a single personal computer, phone phreaking requires more extensive preparation that includes software, hardware, and social engineering expertise. One moment you may be reprogramming the phone company's computers, another you may be soldering wires together to alter a pay phone, and still another you may be chatting with a telephone employee to get the passwords for a different part of the phone system. Like computer hacking, phone phreaking is an intellectual game where players try to learn as much as they can about the system (usually) without breaking any laws to do so.
Although much of the phone phreaking methods described in this part of the book are obsolete, much of the techniques that phone phreakers invented, such as social engineering, are still valid today. So read this section with the eye of a historian to see how people hacked their way through the telephone company's computers armed with nothing more than their wits and a rotary telephone.