What do you guys think of this idea?
Using Bitcoin as a Decentralized Digital Time Stamp Service.
This has been kicked around a few times in other forum posts (like here
as just a couple of examples). But I think I have an implementation proposal that may be original.Background on Digital Time Stamps (skip or skim if you know this):
The problem that would be solved is this: You have created some digital work (perhaps a photograph, an MP3, or a signed contract, or a word document, or a scanned document). You want to be able to prove that it existed prior to some date.
The old fashioned way to accomplish this would be to snail-mail it to yourself in a sealed envelope, and use the postmark as your proof.
A newer technique is to use a digital time stamp service such as digistamp
. Digital time stamping Protocol is described in rfc 3161
.Costs to time stamp something
can range from about 40 cents for quantity of one, down to about 4 cents or less, at higher quantities.Proposed Bitcoin solution:
If you have a digital file that you wish to time stamp, perform the following steps:
1) calculate a digital hash of the file, to generate a unique Bitcoin Address
2) pay that address some very small amount of Bitcoins (somewhere between .00000001 and .01 BTC, along with the appropriate transaction fee).
This payment would effectively be destroyed, as the likelihood that anyone has that address in their wallet would be extremely small. The value of everyone else's Bitcoins would rise ever so slightly (as supply would be reduced), which should make many of you happy. There's no extra burden on the Bitcoin system (as would be if you stuck additional information in the transaction record). The only burden would be a small transaction, which would be funded by the transaction fee.
To defend your claim of the time stamp, you'd simply need to show that the digital hash (fingerprint) of the file equals the address that the coins were sent to.
To prove that you "own" the digital file (if necessary), you'd simply need to show that you are in control of the sending Bitcoin address (so you'd need to save your wallet file). This claim would obviously not be as strong as the timestamp claim, as you could have stolen the wallet file.Pros and Cons:
When compared to other digital time stamp services, this can be much cheaper. It is decentralized. But it is not RFC 3161 compliant. And it wastes/destroys small amounts of Bitcoins.
Any comments? Any ideas for improvement?