Re:Excoin exchange's Bitcoins stolen, will be shutting down
by ChuckMcM on Sunday February 15, 2015 @03:50PM
(#9054055)
> Bitcoins are just sequences of ones and zeros.
Not exactly, and that is what makes them interesting. The ones and zeros are part of what is essentially a digital 'tally stick' [1] where the account has a set of them and there is this globally shared data structure which has a matching set of them.
There is some secret data the user has which allows them to "unlock" their ones and zeros and rewrite them so that they can rewrite them to say "these are not my ones and zeros". And that transaction is combined with another one of the form "these ARE my ones and zeros", and after a minimum number of copies of the global list has that information the transaction can be said to be complete.
If the user were to attempt to reassert their ownership of the ones and zeros (they have all of the original data still) the global list which everyone else can see shows that have given up those ones and zeros in the past. And there is nothing the user can do to change the global list at that point. Its like the master tally stick was swapped out in the vault and their half no longer matches any part of it.
There is some secret data the user has which allows them to "unlock" their ones and zeros and rewrite them so that they can rewrite them to say "these are not my ones and zeros". And that transaction is combined with another one of the form "these ARE my ones and zeros", and after a minimum number of copies of the global list has that information the transaction can be said to be complete.
If the user were to attempt to reassert their ownership of the ones and zeros (they have all of the original data still) the global list which everyone else can see shows that have given up those ones and zeros in the past. And there is nothing the user can do to change the global list at that point. Its like the master tally stick was swapped out in the vault and their half no longer matches any part of it.
[1] http://en.wikipedia.org/wiki/Tally_stick