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Comment by NoGravitas | Hacker News Reader

I generally agree with you, but there's one problem with the physical key analogy. The security of physical keys is weak enough that there's always a fallback if you lose all the copies of your key: you pay a locksmith to come pick the lock and rekey it.

You can't do this with digital keys because a digital key that is weak enough for this strategy to be usable is also too weak to protect you from the main class of attacks it's supposed to be protecting you from.

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> there's always a fallback if you lose all the copies of your key: you pay a locksmith to come pick the lock and rekey it.

In the digital world you have Shamir's Secret Sharing. Generate a non-encrypting, non-signing, decode-only key and give a N-th of if to N escrow services. If you lose your key you contact M of those entities and recover the data.

Plenty of tricks have been created in the last two decades to address the problems associated with key ownership, the problem is always the lack of UI and of standardization in general.

These escrow services would be centralized targets too just like Microsoft, Google, Amazon, etc.

I think the idea is that you store only part of the key with each service, and you're the only one who knows which services have which parts--so, you're the only one who can reconstruct the key. Of course, the UI is still a problem.

Who says you need escrow services for that?

Store your N'th fragments with /friends and family/ that you know well. You might also be able to get in on distributed backups together.

Here comes Facebook Key Escrow?

Thanks. I did not know that.

Sure, as I mentioned, the physical key analogy isn't a perfect match. I'm jsut suggesting that there are some clear starting places where it should be possible to leverage existing skills, instead of starting from scratch. The details about a actually-usable product will be more complicated (and probably requires some experimentation).

Why not print the key?

This may actually be a very good idea for some cases.

If the stuff being protected by the key is, for example, the type of data that someone would otherwise keep in a personal fire-safe, then simply printing out the keys and keeping them in that fire-safe wouldn't change the type of security being provided.

It might be nice if we had some type of highly-reliable (like the redundancy in QR codes[1]), so the process of printing out a key and re-scanning it was easy and trustworthy.

[1] http://datagenetics.com/blog/november12013/index.html

You could just use a QR code. There's no real reason they need to be URLs.

I've tried this. Turns out that very few QR-code readers are able to cope with QR-codes large enough to hold a decently sized RSA key.

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