Classic Cryptography Key-Based Encryption   Symmetrical Key   Assymetrical Key   RSA   IDEA, RC2 and RC4   DES   Pretty Good Privacy    (PGP)   How public key works    mathematically   Glossary Basic Concepts in Data Encryption: Key-Based Encryption About the author About the author History of PGP How PGP works Philip R. Zimmermann, the renowned author of the PGP program, got into trouble for releasing this encryption program to the public. However, in 1996, two years after he was first charged, the US government dropped the charges against him. He joined CEBus right after college, but in 1980, quit his easy going consultant job to start a business with some friends, Metamorphic Systems. Conception of idea The hot new computer of the eighties was the Apple II, by Apple Computer. The Apple II had a full-size keyboard, flashy graphics, and a speedy 6502 microprocessor. As time went by, that 6502 seemed to run slower, and slower, and slower. When IBM kicked out its PC in 1981, it used the new 8088 processor from Intel. Zimmermann’s start up company had a simple idea. Create a card that would effectively upgrade the 6502 Apple II by adding a 8088 in the back of the computer. One day, Zimmermann got a phone call from a computer programmer in Arkansas named Charlie Merritt. He needed the speed for a clock cycle hog, a public key cryptography system, called RSA. Merritt’s call to Metamorphic was actually a marketing gimmick. He was incredibly lucky. Zimmermann happened to have a boyhood interest in encryption. The two hit it off. Merritt turned out to be a natural in mathematics and Zimmermann not. For a long time Merritt taught Zimmerman about mathematics. Now it was time for Zimmermann to meet the Public Key. In the summer of 1986, Merritt and Zimmermann decided to meet. Merritt was to fly up to Boulder for a week to teach Zimmermann the details of doing multi-precision ( 0.00000… ) arithmetic on a computer. Zimmermann was thinking of writing an implementation of RSA on an IBM PC. Merritt also arranged for both of them to meet Jim Bidzos, the president of RSA, while there were problems with this meeting, we’ll cover those in the legal section. Briefly, Zimmermann claims that Bidzos offered a free license for RSA to him, and Bidzos says he didn’t. Either way, Zimmermann didn’t have a license, but made PGP Version 1.0 anyway. The story continues. Zimmermann gave a copy of PGP to a friend to evaluate, and he posted it on Usenet, a www for UNIX network. PGP was tossed to the wind. Bidzos was not happy. An agreement was signed that RSADSI would not sue Zimmermann if he discontinued distributing PGP. PGP became a main competitor with RSADSI’s MailSafe program, not important to RSADSI by 1991, Bidzos was out to protect his patent, but PGP spread and spread and spread. Copyright ©1999 ThinkQuest Team 27158 — Developed for ThinkQuest 1999