This is the ultimate modern cipher, and it has several variants. This cipher, used world-wide, has two keys: one public and one private. The public key is a large number available to everyone. The number is special in that only two whole numbers (apart from 1 and the number itself) will divide into it perfectly. These two numbers are the private key, and if multiplied together, produce the public key. So the public key might be 1961, and the private key 37 and 53. The public key is used to encipher a message, but it is impossible to decipher without the private key. When you email personal details to a bank, or when your bank card is read by a machine, the details are enciphered this way and only the bank can access them with their private key. The reason this is so secure is that mathematically it is very difficult to find divisors of large numbers. To help security, until recently RSA Laboratories gave money to anyone who could find the two divisors of the numbers they gave. For a relatively easy example, once worth $1000 USD, try to find the two 50-digit divisors of 1522605027922533360535618378132637429718068114961
380688657908494580122963258952897654000350692006139.
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Codes and Ciphers
RandomThe need to conceal the meaning of important messages has existed for thousands of years. Over time, people have found increasingly complex ways of encoding their messages as the simpler ways are decoded with greater ease. Contrary to layman-speak...
