3 ms·

What if AES-128 is used? The expected keys to check then is just 2^64.

• kragen 2y ago
  2¹²⁷ nanoseconds would be only 390 billion times longer than the universe has existed so far (13.79 billion years). If you wanted to crack AES-128 with brute force using one-billion-key-per-second cracking computers and could only wait a year, you would need 5.4 sextillion computers. If each of those computers weighed 100 milligrams, in the neighborhood of many current chips, their total mass would be 539 trillion tonnes (5.39 × 10¹⁸ kg, 539 exagrams). That's only about a hundred thousandth of the mass of the Moon, and there are dozens of asteroids larger than this. Since it's clearly physically possible to disassemble an asteroid, or even the entire Moon, and build computers out of it, AES-128 should not be considered secure against currently known attacks. However, currently, it is not publicly known that the NSA has converted any asteroids into computers, and it seems unlikely to have happened secretly.
• kuratkull 2y ago
  Example with smaller numbers: 2^10 / 2 = 512 512 is 2^9 So when dividing powers like this you decrement the exponent. So no it's not 2^64 but more like 2^127 Dividing a loooong number with a small number has virtually no impact on the number.
  • OutOfHere 2y ago
    My apologies for my flagrant error. Thank you for the correction and clarity.