2

Let's say I am using a RSA keypair to encrypt and decrypt a large amount of traffic over a public network. Assume all traffic is padded and the key is 2048 bits, how often would you recommend renewing the private key?

Is there a mathematical solution to how much encrypted data is needed in bytes that would allow a hacker to calculate the private key?

A real life example of this might be a messaging service which encrypts all traffic with one key.

Improve this question
9
  • 1
    See here, which states "In 2009 the 768 bit number rsa-768 was cracked using about 1000 cores and 2 years of calculations. Assuming they used the General number field sieve (a very fair assumption) it would take them 7481 years to crack a 1024 bit number using the same hardware."
    – Robert Harvey
    Jan 13, 2017 at 17:16
  • @RobertHarvey: So... renew every 7000 years, just to be safe? ;)
    – FrustratedWithFormsDesigner
    Jan 13, 2017 at 17:39
  • 2
    Something like that. 2048 bits is probably closer to "heat death of the universe."
    – Robert Harvey
    Jan 13, 2017 at 17:39
  • @RobertHarvey assuming that particular configuration. If you increase the computational power involved you can reduce the time to break the key. Other aspects have to be considered like a leak of your keystore.
    – linuxunil
    Jan 13, 2017 at 17:52
  • 5
    I think this should be migrated to Information Security.
    – JimmyJames
    Jan 13, 2017 at 21:32

0

Reset to default

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Browse other questions tagged or ask your own question.