Public key cryptography is a revolutionary method of sending secret messages that has been used for thousands of years. In the past, people would scramble their messages using a special rule known only to them and their intended audience. However, this method had a major flaw – how do you get the key to the right person without it falling into the wrong hands? The solution to this problem is public key cryptography, which relies on making the key widely available instead of keeping it a secret.
This method works by using two keys – a public key and a private key. The public key is used to scramble the message, while the private key is used to unscramble it. This is similar to using two complementary ingredients in an invisible ink – one makes the message disappear, and the other makes it reappear. Anyone can make messages disappear, but only the person with the private key can make them reappear. This ensures that the message remains secret and has not been deciphered along the way.
In public key cryptography, the public and private keys work like the two ingredients in the invisible ink. However, instead of using chemicals, it uses mathematical puzzles called trapdoor functions. These functions are easy to compute in one direction but extremely difficult to reverse. They also contain trapdoors, which are pieces of information that make the functions easy to compute in both directions if known. One common trapdoor function involves multiplying two large prime numbers, which is easy to do but difficult to reverse.
In conclusion, public key cryptography is a secure and efficient way of sending secret messages. It has replaced the traditional method of scrambling messages and has made it possible to share keys without compromising their security. This method has revolutionized the way we communicate and has made it easier to keep our messages private.
