Timed Encryption

There has been a lot of talk about how quantum computers may break all of our current encryption algorithms. But there are ways to develop encryption algorithms that can’t be easily cracked by quantum computers.

I’m not going to pretend that I know much about encryption. I have undergraduate degrees in computer science and mathematics, but I’m admittedly weak on the cryptography knowledge. But I have an idea for how we can prevent brute-force attacks.

What if we could develop an encryption algorithm that can only be unlocked at certain times. As an example of how this might work, imagine you have a safe. The safe is a physical safe. You know, that big metal box with a combination lock on it.

Now imagine that you set a five-digit password for the combination lock, ranging from 00000 to 99999. There are 100,000 possible combinations. If you were a burglar who stole this safe, you could bring it back to your secret lair and crack it by “brute force.” That means just sitting there and trying each and every possible code combination. If it took you a second to try each combination, you could get through all 100,000 combinations in under 28 hours. You would probably hit it earlier, probably around the 14th hour. So it’s definitely possible to crack the safe with brute force.

But what if the safe was designed so that it would only open at certain times, whether you have the correct password or not? There are many ways to do it. Maybe you set it so that it will only open on Saturdays. Or only between 11am and noon. Or only at times ending with a “5.” The specific time instruction could also be kept secret like the passcode. Doing this would effectively destroy any confidence someone might have in the brute force method of cracking. After all, even if you guess the right passcode, but at the wrong time, you would still not get in. Not only that, but you would cross the correct passcode off your list of possible correct passcodes, even though it is correct. You could spend 28 hours going through all 100,000 possible combinations, but still not be able to open the safe.

I say all this with one big caveat: it may or may not be possible to create such an encryption algorithm. I simply don’t know enough about the topic to know if it’s possible or not.