RSA

tags

Security

Summary #

The Rivest-Shamir-Adleman (RSA) encryption algorithm is an asymmetric encryption algorithm (Asymmetric Cryptography) that is widely used in many products and services. Asymmetric encryption uses a key pair that is mathematically linked to encrypt and decrypt data. A private and public key are created, with the public key being accessible to anyone and the private key being a secret known only by the key pair creator. With RSA, either the private or public key can encrypt the data, while the other key decrypts it. This is one of the reasons RSA is the most used asymmetric encryption algorithm. ref

How it works #

The technical details of RSA work on the idea that it is easy to generate a number by multiplying two sufficiently large numbers together, but factorizing that number back into the original prime numbers is extremely difficult. The public and private key are created with two numbers, one of which is a product of two large prime numbers. Both use the same two prime numbers to compute their value. RSA keys tend to be 1024 or 2048 bits in length, making them extremely difficult to factorize, though 1024 bit keys are believed to breakable soon.