27 Feb
2017
27 Feb
'17
8:39 a.m.
On Mon, 27 Feb 2017 07:23:43 -0500, Jon Lewis said:
On Sun, 26 Feb 2017, Keith Medcalf wrote:
So you would need 6000 years of computer time to compute the collision on the SHA1 signature, and how much additional time to compute the trapdoor (private) key, in order for the cert to be of any use?
1) Wasn't the 6000 years estimate from an article >10 years ago? Computers have gotten a bit faster.
No, Google's announcement last week said their POC took 6500 CPU-years for the first phase and 110 GPU-accelerated for the second phase. You are totally on target on your second point. A million node botnet reduces it to right around 60 hours.