My understanding of current blockchain technology is that it’s only permanent so long as someone is online maintaining the block integrity. If enough machines go down, or if enough machines come up that refute it, then anyone can push an alternate history.
It assumes that the stakes are high enough for there to be a significant network online, yes. You could of course still compare your local history to the online one but by then the technology has failed its purpose.
How do you modify a transaction that occurred 100 blocks ago? You’d have to also modify the 99 other blocks since that modification. But for those new blocks to be valid you need to find the new magic number that brings the hash below a certain threshold, 99 times. But there aren’t enough machines.
My understanding of current blockchain technology is that it’s only permanent so long as someone is online maintaining the block integrity. If enough machines go down, or if enough machines come up that refute it, then anyone can push an alternate history.
It assumes that the stakes are high enough for there to be a significant network online, yes. You could of course still compare your local history to the online one but by then the technology has failed its purpose.
A Bitcoin heist where you install a false ledger using a botnet.
False.
How do you modify a transaction that occurred 100 blocks ago? You’d have to also modify the 99 other blocks since that modification. But for those new blocks to be valid you need to find the new magic number that brings the hash below a certain threshold, 99 times. But there aren’t enough machines.