|
|
|
|
|
|
by as300
2828 days ago
|
|
|
>Publishing a DB dump with a checksum has been around for decades This solves the problem of where you would publish said checksum. Instead of publishing it in an issue of the New York Times, say (which could theoretically be forged), you publish it somewhere that you can be 99.99% sure won't be forged, is viewable to everyone, and can be done fairly cheaply and would likely hold up in any court of law. However, that's pretty much it. That's the whole benefit. You could also probably publish said checksum on facebook, with the same likelihood of it not being tampered with. Note that I'm not arguing that blockchain won't gain adoption, just as people probably could have made a similar value-based argument about facebook in its early days, I personally believe there are cultural forces that will keep some blockchain asset in somewhat high demand. |
|
|
That's not quite it. The other thing you get is "and this database guaranteed to have some properties". In the case of bitcoin for example you are guaranteed every transaction was authorised by the owner of the bitcoin being exchanged and there are no double spends.
But even that's not quite it, because those properties are flexible - even for bitcoin. They are actually assertions made by computer programs, something the lines of "if the database says X an Y are true, then I say Z is true". For example X might be "I have the put $x in an escrow account". Y might be "I have not paid the supplier $x in the agreed y days". Z might be "The escrow agent is allowed to deduct an fee from $x for himself, and pay the balance to myself and the supplier as he sees fit".
And thus we have gone from publishing the checksum of a database to controlling what can happen to $x in the future.
In general taking a snapshot of a blockchain at a single point in time and saying "all I have done is published an immutable database" misses the bigger picture. The blockchain is a chain of assertions about what has happened in the past and based on those what can happen in the future - and you can't alter the control of those future assertions re-writing the past, which is prohibitively expensive.
We currently have another way of doing a similar thing that has been refined over the centuries - contracts, interpreted by courts rather than software, enforced by governments, police and guns. Right now the new boy on the block, blockchains, only thrives where this existing system refuses to play - which is to say illegal transactions. (And maybe its detractors are right - maybe it will always be too clumsy and slow to expand beyond that.) However to say the blockchain is merely a snap shot of its database rendered immutable by a published checksum is like saying our system of law is a just the series of title deeds on house, rendered immutable because they line in some government office.