What Is the RSA Algorithm?

The RSA encryption algorithm is an asymmetric encryption algorithm. RSA is widely used in public key cryptography and electronic commerce. RSA was proposed in 1977 by Ron Rivest, Adi Shamir, and Leonard Adleman. All three of them were working at MIT. RSA is composed of the letters of the three of them.

RSA public key cryptosystem. The so-called public-key cryptosystem is the use of different encryption and decryption keys. It is a cryptosystem that "deriving a decryption key from a known encryption key is not computationally feasible.

The security of RSA depends on the decomposition of large numbers, but whether it is equivalent to the decomposition of large numbers has not been theoretically proven, because it is necessary to perform the decomposition of large numbers without proof. Assuming that there is an algorithm that does not need to decompose large numbers, it can definitely be modified into a large number decomposition algorithm. Some variants of RSA algorithms have been proven to be equivalent to large number decomposition. In any case, factoring n is the most obvious attack method. People have been able to resolve large primes with multiple decimal places. Therefore, the modulus n must be selected to be larger, depending on the specific application. ^[1]

1. The most popular attacks against RSA are generally based on factorization of large numbers. In 1999, RSA-155 (512 bits) was successfully decomposed, and it took five months (about 8000 MIPS years) and 224 CPU hours to complete it on a Cray C916 computer with 3.2G central memory.

RSA-158 is expressed as follows:

  39505874583265144526419767800614481996020776460304936454139376051579355626529450683609727842468219535093544305870490251995655335710209799226484977949442955603 = 3388495837466721394368393204672181522815830368604993048084925925925 850 142 142 142 142 142 146

On December 12, 2009, the number RSA-768 (768 bits, 232 digits) was also successfully decomposed. This incident threatened the security of the popular 1024-bit key. It is generally believed that users should upgrade to 2048-bit or above as soon as possible. ^[1]

• Public key encryption

• Quantum computer

• Sauer Algorithm