- on General interest
- Published in issue 10/1988 on page 59
DATA ENCRYPTION by Pete Chown Hacking, the illegal accessing of computers, is a crime peculiar to our technological world. It is also becoming more widespread. One way of frustrating hackers is data encryption. Data encryption is a vital part of data security but, since effective codes are not too widely advertised, information on it is scarce. The modern tendency is to design codes where a knowledge of the algorithm used for encoding a message is not suf- ficient by itself to break the code. In such a system, the people exchanging messages agree a key in advance, which might be a string of 20 random bytes. Hackers not knowing the key will not be able to break the code, even if they know the algorithm. In this article, I will outline a code that I have developed for private purposes. It uses a key that can be any length, de- pending on the level of security required, up to the length of the message being transmitted. For simplicity"s sake, I will, however, assume a 20-byte key. If...