101–110 of 149 posts
Here's a way to encrypt something with an actual timelock, which works because physics. More specifically, it works because there is a maximum speed that information can travel through space: the speed of light. Step 1: Generate a large number of named public/private keypairs and put the private keys on a spacecraft. Also give the spacecraft a communication system and a long-lived RTG (an energy source getting its en…
The only way that I know to encrypt something into the future is generating an N-bit key and hoping someone will go through the trouble of cracking it when that becomes feasible. That involves lots of assumptions (e.g., how computing power develops and how much that person cares). The website's implementation is this: > A group of [orgs] holds the keys. There are 18 separate organizations running a total of 22 nodes,…
That's an interesting idea. Similarly, you could make a sort of quantum time capsule by encrypting a blob of data with RSA or ECC and publishing the cyphertext alongside the public key. You could even adjust the key size depending on how powerful you want the quantum computer that decrypts it to be.
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You can just use desktop/laptop CPU accelerated sha256, iterate the round function for as long as you want. No hardware exists that can beat it on latency by any significant margin. Start with some random 256-bit string as the seed. Iterate on it for t time using sha256 CPU instructions - by either repeatedly hashing the seed or increasing the number of rounds to an arbitrary value (and do something about the round c…
But it also take t time to encrypt?
The trapdoor method is successive squaring and relies on quite a few assumptions for its security.
The hash method also has the advantage that the sender can utilize multiple machines/cores in creating the encrypted package. By executing the serial hash task in parallel with all available resources and using the results of each chain to encrypt each other in another chain.[1]
[1] https://news.ycombinator.com/item?id=7848999>
It’s an interesting property of the universe that there’s no way to measure time directly. It clearly exists, yet all you can measure is change of things besides time. Time lock puzzles take variable time depending on hardware. You can’t really set an accurate specific release time. Any change in the universe that a computer can detect is just another spoofable input. Blockchain tries to solve essentially the same pr…
Earlier quoted context omitted.
From the actual problem description: Note that the puzzle can be solved by performing t successive squarings modulo n, beginning with the value 2. That is, set W(0) = 2 W(i+1) = (W(i) ^ 2) (mod n) for i=1, 2, ... and compute W(t). There is no known way to perform this computation more quickly than to perform the t squarings sequentially, unless the factorization of n is known.
Ah! Thanks. That immediately answers the second thing I was wondering about, since 2k RSA keys are still deemed safe (if barely / not for secrets that need to last a long time into the future)
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My inner devil likes the "too dangerous to approach" idea :) About the last idea, I had to look up that name: > James Riddle Hoffa (born February 14, 1913; disappeared July 30, 1975; presumed dead July 30, 1982) was an American labor union leader who served as the president of the International Brotherhood of Teamsters (IBT) from 1957 until 1971. Do I read it correctly if I understand "Jimmy Hoffas pocket" to be one…
Yes, Jimmy Hoffa is a "famous" disappeared person case here in America. There are only a few "famous mysteries" that became such widespread memes in American culture. The ones I can think of are: 1. What happened to Jimmy Hoffa (who killed him?). "The Irishman" on Netflix is a Scorsese adaptation of a "nonfiction" book that documents an old Mafia hitman claiming to have killed Hoffa. (The book is nonfiction, the guy'…
Rivest, Shamir and Wagner, 1996: "Time-lock puzzles and timed release Crypto" https://people.csail.mit.edu/rivest/pubs/RSW96.pdf FWIW it took me about 3.3 years of computation (on one core, it's not parallelizable), from about 2015/2016ish to 2019, to find the solution to Rivest' LCS35 problem (which he created in 1999, so I found the solution 20 years after he created that LCS35 puzzle): https://en.wikipedia.org/wik…
There are solutions which don’t require a third party. These would be guaranteed to survive in case a third party shuts down with a long duration. Paper: https://docs.google.com/document/d/e/2PACX-1vQe-OF0Lw9lutf6a...
I’m really not convinced that solution is better is any way. If your adversary has the resources to coerce the “leave of entropy” in the OP, cracking that blockchain implementation will be trivial.
It’s an interesting property of the universe that there’s no way to measure time directly. It clearly exists, yet all you can measure is change of things besides time. Time lock puzzles take variable time depending on hardware. You can’t really set an accurate specific release time. Any change in the universe that a computer can detect is just another spoofable input. Blockchain tries to solve essentially the same pr…
What about time crystals? https://en.wikipedia.org/wiki/Time_crystal
The only way that I know to encrypt something into the future is generating an N-bit key and hoping someone will go through the trouble of cracking it when that becomes feasible. That involves lots of assumptions (e.g., how computing power develops and how much that person cares). The website's implementation is this: > A group of [orgs] holds the keys. There are 18 separate organizations running a total of 22 nodes,…
> You can’t hide secrets from the future with math
> You can try, but I bet that in the future they laugh
> At the half-assed schemes and algorithms amassed
> To enforce cryptographs in the past