I like the idea, altough I think (Im not sure) there are already some options after your death, maybe search on funeral.

When you realy are able to secure the stuff, why can't you ask some money? Will be a nice site and indeed very attractive for hackers. A lot of people will be curious what others have saved on the site. Maybe actually that's the trigger to get the whole world on the site :-)

About security, not my cup of tea, but hopefull someone here can help.

Perry

Perry is right about hte security part although you can keep information off-line and only put it on-line after the date that you choose.
The problem is when someone kills me, how do I notify you that I'm dead?
Tommy

No notification necessary, you just say "publish this in 100 years" or something (small risk to still be alive by then - too bad). OK, the other scenario would also be interesting, publish at time of dead. Might be an interesting extension of the business. Although I suppose traditionally this was done through lawyers, at least that is what I have seen in movies several times.

I am now also thinking, maybe I could only store the keys for the coming year on the server, and the others in the vault of a bank. That should be fairly secure at least for the messages that reach into the future further than one year. I would still need to make sure that the service keeps running even if I could not attend to it personally (ie in case I die). An interesting challenge to set up an organization that can guarantee to still be in service 50 years from now.

From a technology side, the cryptography is easy. Like you said, a daily public key pair would accomplish it. But you're also right that keeping those key pairs secret until the appropriate time is a very hard problem. You have two very big problems in that regard: internal and external threats.

For internal threats, you have to convince me that you are trustworthy. Nevermind whatever security you put in place to keep the keys secret from the public; I have to trust you with my info. If you have the keys already generated (which is required if you're going to publish the part of the key for me to encrypt with) then I'm basically telling you my secret and asking you pretty-please not to tell. Why would I do that? Convincing me is an enormous marketing challenge and one slip blows the whole deal.

For external threats, I'd worry less about bad guys with rubber hoses and more about law enforcement officers with warrants. There's no way your key store would stand up to a legal challenge of privilege, so the first time any authority is interested in any of your users, they'll get a warrant for the key(s). At that point (IMO) the entire system is compromised because then not only do I have to trust you, but I have to trust every member of every LEO that's seen your keys. While I trust LEOs in general, it would be naive to assume that every individual officer is absolutely trustworthy not to misuse data obtained by warrant.

However, this is a very interesting problem. I wouldn't be surprised if some big-brain cryptographer had come up with some elegant solution to do exactly what you propose in a secure way. It might be worth posting the question on a crypto forum or mailing list because this is just the kind of thing they like to conjecture about.

One inelegant solution would be to make your keys of different sizes and then destroy the private key of each pair. You could then set some big iron to the task of breaking each key. You could say that a key of x-bits is probably secure for a year, a key of y-bits is probably secure for five years, etc. (barring any breakthrough in factoring or calculation). This makes it more of a novelty than a day-by-day service provider, but at least you could have some amount of security that no one could get your keys without devoting extraordinary cracking effort.

I like the idea to destroy the private key and leave it all to computation time ;-) But there is another problem anyway: the biggest supercomputer of the world is currently owned by hackers. It is called Storm, a network of hacked personal PCs. Therefore I wonder how secure any encrypted information is anyway? Perhaps Storm could crack anything they want in relatively short time. Maybe not, though - I'd have to do the calculations.

In any case I think it would be impossible to provide a key that would hold up for 100 years. Maybe 30 years into the future would be doable - again, I would have to do some research about the current state of the art.

I don't think Storm or any other botnet is a big concern. Yes, they dwarf most of the other grid computing solutions, but they have a vested interest in staying under the radar. As soon as they start to peg those machines with hard computations, more people will realize they're compromised and take basic security measures. The spam and DoS trades are far to profitable to risk a botnet for something like cracking encryption keys unless there is a guaranteed payoff.

yeah a fun project ..and CH community mostly dislike a "nonprofitable" concept...

Goodluck anyway!

If it is technically possible, I like this idea. Perhaps people will add thoughts that they would like releases in a month a year or 100 years.

Kind of a legacy.

I think this is being done already...i read it somewhere and also some e-cards services have advance delivery date that do the trick.

joyce, I've seen several services that offer advanced delivery dates, but not in any secure way like is being described here. Sending an ecard with a delivery date in the future is almost trivial. Keeping the content secure before that date is another problem entirely as discussed above.

If you've seen services that offer what this idea describes, I'd be very interested in seeing how they're solving those problems.

Maybe the key can be distributed on a P2P network? Or a key to the key? Somehow distribution might alleviate warrant fears (parts can reside outside of any one jurisdiction). I know that's not a solution but maybe its part of a solution.

there is something like this: http://www.futureme.org/

Imagine if all of the private keys had been put on a spacecraft like Voyager. Then each day it would transmit that days private key back to earth. Because it is going very fast away from earth and has a huge head start it would be next to impossible to catch it. Even if someone in a hundred years designed a spaceship that could go so much faster that it could catch it, it would be very very hard to launch such a chase ship without everyone knowing.