Is it rewritable, or is it append only? You only wrote one sentence yet still managed to contradict yourself so I suspect you have a very meager comprehension of the technology.
As I understand, it’s normally append-only. But, with some implementations, if a malicious entity controls most of the block production, they can undo recent transactions at will.
Some resort to majority vote, in the case of disagreements. Theoretically, if someone owned/controlled over 50% of the database, they could rewrite it, and have their version seen as true.
For the few valid uses of it, that shouldn’t be a problem. It will also be reasonably detectable beforehand.
It’s not as simple as that. Each block solves the problem of the former block, so to change something five blocks back, you now need to solve six blocks prior to writing the next block, otherwise it’s not cryptographically valid. The resources required to accomplish that are not trivial, and it’s never been done. Very theoretical indeed, in the same sense you could theoretically run through a wall if all of your atoms missed all of the atoms in the wall when you should have collided.
Go ahead and prove me wrong. Show me blockchain implementations that are immutable post append. On my end, we can talk about Bitcoin forks. We can also talk about the current state of consensus mechanisms, each of which has the explicit ability for large actors to rewrite history in their favor. Even Monero is susceptible because this is fundamental to the blockchain in any form. It’s been a huge reason why I make sure I get paid up front for any consulting I do in this space.
Only the last few blocks are “rewritable,” which is why a certain number of confirmations are a necessity. Going any further back than that, would be a completely different chain - a fork. The last of of those occurring on Bitcoin was thirteen years ago when it was still encountering growing pains due to an uptake in usage. Forks of more than a couple transactions are not a frequent, regular occurrence by any exaggeration, so for all intents and purposes of modern crypto usage, it is immutable, not "rewritable.’
Notice I put quotes around rewritable. That’s because it’s not the correct term, and I was being charitable in engaging in your straw man argument. It’s actually a collision of timing, where two solutions are presented for the same block in a short amount of time, and until the consensus is reached by the majority, both are temporarily valid. Once consensus is reached, it’s final. There’s no going back. In that sense it is not rewritable, it is immutable. It’s just fuzzy for the first fifteen minutes which branch will resolve as the actual Blockchain in the event of near ties.
You’re naively referring to how consensus should work while completely ignoring both the well-defined attacks I referenced and the reality of large actors in a consensus network. You don’t know what you’re talking about or you don’t understand how the theory works or you’re possibly just being obtuse. No matter what, this is pointless. Good luck.
Perhaps I am. I’m referring to your malicious actor you believe will rob you of your holdings. What does that look like? Some nebulous entity undertakes the task of acquiring greater than half of the processing power of the Bitcoin Blockchain, expending enormous resources to do so, for the purpose of reverting the $500 they paid you? And they’re not at all worried about devaluing the network they’ve invested significant resources into controlling, they just want their $500 back? The attacks are theoretical because they’re not practical and require illogical actors working against their own interests by undermining the network they’re supporting. It would be like a bank who takes deposits, but doesn’t allow withdrawals - who would trust them? They’d go bankrupt for their efforts.
Is it rewritable, or is it append only? You only wrote one sentence yet still managed to contradict yourself so I suspect you have a very meager comprehension of the technology.
As I understand, it’s normally append-only. But, with some implementations, if a malicious entity controls most of the block production, they can undo recent transactions at will.
Some resort to majority vote, in the case of disagreements. Theoretically, if someone owned/controlled over 50% of the database, they could rewrite it, and have their version seen as true.
For the few valid uses of it, that shouldn’t be a problem. It will also be reasonably detectable beforehand.
It’s not as simple as that. Each block solves the problem of the former block, so to change something five blocks back, you now need to solve six blocks prior to writing the next block, otherwise it’s not cryptographically valid. The resources required to accomplish that are not trivial, and it’s never been done. Very theoretical indeed, in the same sense you could theoretically run through a wall if all of your atoms missed all of the atoms in the wall when you should have collided.
Go ahead and prove me wrong. Show me blockchain implementations that are immutable post append. On my end, we can talk about Bitcoin forks. We can also talk about the current state of consensus mechanisms, each of which has the explicit ability for large actors to rewrite history in their favor. Even Monero is susceptible because this is fundamental to the blockchain in any form. It’s been a huge reason why I make sure I get paid up front for any consulting I do in this space.
Only the last few blocks are “rewritable,” which is why a certain number of confirmations are a necessity. Going any further back than that, would be a completely different chain - a fork. The last of of those occurring on Bitcoin was thirteen years ago when it was still encountering growing pains due to an uptake in usage. Forks of more than a couple transactions are not a frequent, regular occurrence by any exaggeration, so for all intents and purposes of modern crypto usage, it is immutable, not "rewritable.’
If any of it is rewritable, none of it is immutable. You can’t have it both ways.
Notice I put quotes around rewritable. That’s because it’s not the correct term, and I was being charitable in engaging in your straw man argument. It’s actually a collision of timing, where two solutions are presented for the same block in a short amount of time, and until the consensus is reached by the majority, both are temporarily valid. Once consensus is reached, it’s final. There’s no going back. In that sense it is not rewritable, it is immutable. It’s just fuzzy for the first fifteen minutes which branch will resolve as the actual Blockchain in the event of near ties.
I don’t think you’re using straw man correctly.
You’re naively referring to how consensus should work while completely ignoring both the well-defined attacks I referenced and the reality of large actors in a consensus network. You don’t know what you’re talking about or you don’t understand how the theory works or you’re possibly just being obtuse. No matter what, this is pointless. Good luck.
Perhaps I am. I’m referring to your malicious actor you believe will rob you of your holdings. What does that look like? Some nebulous entity undertakes the task of acquiring greater than half of the processing power of the Bitcoin Blockchain, expending enormous resources to do so, for the purpose of reverting the $500 they paid you? And they’re not at all worried about devaluing the network they’ve invested significant resources into controlling, they just want their $500 back? The attacks are theoretical because they’re not practical and require illogical actors working against their own interests by undermining the network they’re supporting. It would be like a bank who takes deposits, but doesn’t allow withdrawals - who would trust them? They’d go bankrupt for their efforts.