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Questions tagged [timed-release]

Time-lock puzzles and other cryptographic schemes intended to ensure that a message cannot be read until a certain time has passed.

2
votes
1answer
39 views

Time locked cryptography using Bitcoin difficulty param and/or smart contract?

Outcome: Create a message with a count down timer. Once a top level password is entered, a countdown timer starts. Once timer expires, the message is decrypted. Known methods: Proof of work. ...
1
vote
1answer
96 views

Could time lock encryption be implemented through indistinguishable obfuscation?

In the paper "How to build time-lock encryption", the authors give a theoretical solution to build time-lock encryption using multi-linear based witness encryption and blockchain. However, an ...
5
votes
1answer
154 views

How would we design a fast circuit to solve LCS35?

LCS35 is a time-lock puzzle, stated in Ronald L. Rivest's Description of the LCS35 Time Capsule Crypto-Puzzle [1] (April 1999). That instantiates a system in Ronald L. Rivest, Adi Shamir and David A. ...
0
votes
1answer
155 views

Create a time capsule using a Word processor

I was wondering if there's any option to create sort of a time capsule in a Word document, i.e. not encrypted by password rather than a date. Let's say I send the document today but the receiving side ...
0
votes
1answer
67 views

Time-release Protocol Implementation

“How to Build Time-Lock Encryption” by Jager “Time-release Protocol from Bitcoin and Witness Encryption for SAT” by Liu, Garcia, and Ryan I looked through the references, googled, searched GitHub ...
1
vote
0answers
44 views

Can I use a blockchain to lock access to some information before a certain amount of time has passed, without relying on third-parties?

Picture the following (the example is very similar to the real scenario): I have a physical item in possession in which I want to lock myself (don't ask [1]) from accessing it until a ...
2
votes
0answers
68 views

How can I generate a deterministic evenly distributed random number in a blockchain

Here's the hypothetical. There's a blockchain, which for the sake of simplicity, is modelled around Bitcoin and proof-of-work. My goal, is that for each mined block, rather than a set reward (12.5 ...
5
votes
1answer
294 views

Time Based encryption [duplicate]

Looking for the language to describe a solution I am looking for... As a systems admin for an educational institution, I would like to: a) post our tests in an encrypted form b) at a certain time, ...
5
votes
1answer
367 views

Time-locked Puzzles & Dead Man's Switch Intervention

I have been researching time-based puzzles. Specifically, computationally expensive algorithms for the purpose of a time-lock. This has lead me to sequential squaring, firstly, as well as some memory-...
14
votes
1answer
1k views

Dead-Man's Switch Cryptography?

I was looking at Time Capsule cryptography? and came up wth this idea. Question: Is there a way to store a secret such that the creator must update it or the secret will be decrypted and anyone can ...
3
votes
1answer
392 views

Sequential public key generation with secret private keys?

So this is an idea that popped into my head the other day and I wonder if there are any known crytographic schemes with these properties? Is there a way to construct a public / private key system in ...
2
votes
1answer
144 views

Slow encryption (or reverse time-lock)

Are there cryptographic scheme where encryption is sequential and take a long time (in a way that it can be quantified) while instead decryption with a secret key takes very short time? Some sort of ...
1
vote
1answer
439 views

Time-based Crypto [duplicate]

I'm wondering if there is any way to make crypto based on time, where the concept of time is linear in one-direction. Even a theoretical brainstorm. Example 1: A message which can only be opened/...
0
votes
1answer
468 views

Timelock puzzle improvment

I came across this question with this answer about a cryptographic timelock-puzzle that needs approximately 30 years to be solved. There is also an explanation with source code for that puzzle ...
5
votes
2answers
272 views

Ways to make a “doomsday” cryptocurrency which becomes untradable

As a social experiment (not a money-making scheme), I'm interested in developing a crazy cryptocurrency which, by its very design, will become worthless and untradable after a certain point. Ideally, ...
5
votes
2answers
840 views

Why is time-lapse cryptography not popular?

Time-Lapse Cryptography has been introduced by Michael Rabin and Christopher Thorpe in the paper “Time-Lapse Cryptography”, but it does not seems to be popular. It is a really good paper with an great ...
2
votes
3answers
294 views

Decryption possible only within a period of time

Time-locked encryption and time-released encryption seem to be security systems focused on making sure that the decryption of certain message cannot take place before a certain time has passed. ...
17
votes
4answers
4k views

What is the progress on the MIT LCS35 Time Capsule Crypto-Puzzle?

Ron Rivest posed a puzzle in 1999. MIT LCS35 Time Capsule Crypto-Puzzle. The problem is to compute $2^{2^t} \pmod n$ for specified values of $t$ and $n$. Here $n$ is the product of two large ...
14
votes
9answers
12k views

Is it possible to make time-locked encrytion algorithm?

I'm not sure if what I'm asking is even a valid question but here goes. Would it be possible to add a mechanism to an encryption algorithm that would mean it had to be a certain time of the day or a ...
161
votes
20answers
22k views

Time Capsule cryptography?

Does there exist any cryptographic algorithm which encrypts data in such a way that it can only be decrypted after a certain period of time? The only idea that I can think of, is something like this: ...