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How long should an RSA key be?
2048-bit
Since 2015, NIST recommends a minimum of 2048-bit keys for RSA, an update to the widely-accepted recommendation of a 1024-bit minimum since at least 2002.
What is the minimum recommended size for a RSA key?
For RSA keys, the minimum size for clear RSA keys and secure RSA keys on the public key data set (PKDS) is 512 bits. The minimum size for secure RSA keys on the token key data set (TKDS) is 1024 bits and the size must be a multiple of 256.
How long would it take to crack RSA 2048?
around 300 trillion years
It would take a classical computer around 300 trillion years to break a RSA-2048 bit encryption key.
Which is faster RSA key size or Shor key length?
Also note for ordinary users of the cryptosystem, that encryption/decryption time of 1024-bit RSA is roughly 64 times faster than 1024/4096-bit RSA meaning there’s not going to be a larger key-size where a classical user of RSA gains an significant advantage over a quantum computing attacker.
How big is a 256 bit RSA key?
And while a 256-bit symmetric key should be secure for hundreds, thousands, or perhaps hundreds of thousands of years, no RSA key of any length should be assumed to be secure more than a few dozen years out, since RSA is expected to be completely and utterly broken by Shor’s algorithm.
What does it mean when RSA key has length 2048?
When a RSA key is said to have length “2048”, it really means that the modulus value lies between 2 2047 and 2 2048. Since the public and private key of a given pair share the same modulus, they also have, by definition, the same “length”.
Is there a PKE resistant to Shor’s algorithm?
Types of PKE resistant to Shor’s algorithm exist but none of them seem to have widespread use. One of the most promising is the McEliece cryptosystem which is faster than RSA and can have security grow with key size quickly, except the public key is typically about half a megabyte.