How secure is 256 bit security?
Why Hacker News recommends it
HN uses it as the go-to illustration of just how large 2^256 is.
What it is
3Blue1Brown illustrates how enormous the 256-bit search space is, showing how infeasible it is to find a hash or key by guessing and checking.
Recommended by 2 HN commenters across 3 different months, 2020 to 2023.
What Hacker News said
Strong rec yamrzou · 2021-06 · on “DOJ seizes $2.3M in cryptocurrency paid to the ransomware extortionists Darkside”
I wondered the same thing, so I went looking for answers and found this excellent video by 3Blue1Brown: How secure is 256 bit security? : [this video]
Recommends AareyBaba · 2020-01 · on “The most important scientific problems have yet to be solved (1897)”
We know that life is evolvable because life exists and we know the biochemical mechanisms involved (DNA + cellular biochemistry). Evolution implies a relatively smooth path through "DNA space" from, say for example, an early single cell eukaryote to a mushroom. However the search space is enormous. Even if we account for billions of years of evolution and a trillions of evolutionary experiments each year, a simple random walk with selection through DNA space should go nowhere because of the numbers involved. The curse of dimensionality[0] means there has to be some other principle of nature to make the search space yield a path from one viable life form to another. The search space of life w
Recommends AareyBaba · 2020-10 · on “Room-Temperature Superconductivity Achieved for the First Time”
Large number comparisons are difficult for humans to comprehend. If you simplify life to a DNA strand 256 nucleotide long (for the sake of math comparison) - then the search space is 4^256. To comprehend how large a search space this is watch 3Blue1Brown's explanation [this video]
Cites AareyBaba · 2022-09 · on “US Government Bans Export of Nvidia A100 and H100 GPUs to China and Russia”
Even if you had your GPU-packed Kilo-Google per person multiplanetary Gigagalactic computer guessing numbers for 37 times the age of the universe, it would still have a 1 in 32 billion chance of cracking. [this video]
Cites ChancyChance · 2023-03 · on “SETI@home Is in Hibernation”
What was the RSA crack effort you mention? It doesn't seem feasible, considering finding a SHA-256 collision would take so much compute power we don't have words to describe it, and even coming up with thoughts to frame the problem is hard ( [this video] ). I can't imagine cracking even an RSA2048 key with everyone working on it.