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Viliam Furik · 2022-01-11, 21:29

I am not sure exactly how RSA512 works, and I am not willing to research it for this topic, but from what I know, it uses 512 bits as output. Thus it has 2^512 different possible outputs, which have 2^512 different possible inputs. That is about 1.340781e+154.

If you could test 1,000,000,000,000,000 inputs (keys) per second, you would need about 4.251588e+131 YEARS to check them all. Assuming it would be randomly placed, you would most likely require about half of that or 2.125794e+131 YEARS. That would mean your poor CPU (and many other CPU slaves required for the total throughput of 1,000,000,000,000,000 inputs per second) would need to crunch for what is basically more than Googol of estimated ages of the universe (about 1.54043e+121 ages of the universe).

1.54043e+121 = 15,404,300,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000. This many ages of the universe.

If its output is 512 bits in size, this should be about right. Otherwise, I am sorry, and I'll let others correct me.

2022-01-11, 21:29	#2
Viliam Furik "Viliam Furík" Jul 2018 Martin, Slovakia 2FE₁₆ Posts	I am not sure exactly how RSA512 works, and I am not willing to research it for this topic, but from what I know, it uses 512 bits as output. Thus it has 2^512 different possible outputs, which have 2^512 different possible inputs. That is about 1.340781e+154. If you could test 1,000,000,000,000,000 inputs (keys) per second, you would need about 4.251588e+131 YEARS to check them all. Assuming it would be randomly placed, you would most likely require about half of that or 2.125794e+131 YEARS. That would mean your poor CPU (and many other CPU slaves required for the total throughput of 1,000,000,000,000,000 inputs per second) would need to crunch for what is basically more than Googol of estimated ages of the universe (about 1.54043e+121 ages of the universe). 1.54043e+121 = 15,404,300,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000. This many ages of the universe. If its output is 512 bits in size, this should be about right. Otherwise, I am sorry, and I'll let others correct me.