Quote
On 10 second rounds:
In the past two months there have been 15 reorgs of the blockexplorer.com data-collection node. Assuming that a fork of the block chain resulted in only two branches, and that blockexplorer.com had just a 50% chance of selecting the “correct” branch, that means there has been 30 forks of the block chain in the last two months. That's 30 out of 8928 blocks for July and August, or about 0.336% chance for a given block. Now assuming that the network was not subject to malicious action during this time*, that means that in those 30 instances two blocks were generated close enough in time to be within the network latency. Or put differently, we can calculate the network latency of the current, existing bitcoin network to be: 10min/0.336% = 2.02 seconds.
*If it was, that would only lower the resulting latency.
Extrapolating into the future, we can expect this number to go down, not up. That may be somewhat counter-intuitive, but what we are seeing now is the worst-case possibility. The bitcoin peer-to-peer overlay is not optimized, at all. It is also conceivable that when a crypto-currency goes mainstream, we may see the emergence of fiber-optically connected payment processing nodes that can relay blocks and transactions to disparate parts of the network very quickly.
Further, it's not very clear that an increase in the number of forks would even been an issue. Bitcoin has defenses built into the protocol for resolving such conflicts. It is only when the probability of a split exceeds 50% that the block chain becomes divergent. On the current bitcoin network, that means round times must be no shorter than 4 seconds.
10 seconds is more than twice that lower limit, and as I said that limit will only get *smaller* as the network gets smarter.
more to come...
In the past two months there have been 15 reorgs of the blockexplorer.com data-collection node. Assuming that a fork of the block chain resulted in only two branches, and that blockexplorer.com had just a 50% chance of selecting the “correct” branch, that means there has been 30 forks of the block chain in the last two months. That's 30 out of 8928 blocks for July and August, or about 0.336% chance for a given block. Now assuming that the network was not subject to malicious action during this time*, that means that in those 30 instances two blocks were generated close enough in time to be within the network latency. Or put differently, we can calculate the network latency of the current, existing bitcoin network to be: 10min/0.336% = 2.02 seconds.
*If it was, that would only lower the resulting latency.
Extrapolating into the future, we can expect this number to go down, not up. That may be somewhat counter-intuitive, but what we are seeing now is the worst-case possibility. The bitcoin peer-to-peer overlay is not optimized, at all. It is also conceivable that when a crypto-currency goes mainstream, we may see the emergence of fiber-optically connected payment processing nodes that can relay blocks and transactions to disparate parts of the network very quickly.
Further, it's not very clear that an increase in the number of forks would even been an issue. Bitcoin has defenses built into the protocol for resolving such conflicts. It is only when the probability of a split exceeds 50% that the block chain becomes divergent. On the current bitcoin network, that means round times must be no shorter than 4 seconds.
10 seconds is more than twice that lower limit, and as I said that limit will only get *smaller* as the network gets smarter.
more to come...
Maybe he is on to something?
