If we want to cap the time of downloading overhead the latest block to say 1%, we need to be able to download the MAX_BLOCKSIZE within 6 seconds on average so that we can spend 99% time hashing.
At 1MB, you would need a ~1.7Mbps connection to keep downloading time to 6s.
At 10MB, 17Mbps
At 100MB, 170Mbps
and you start to see why even 100MB block size would render 90% of the world population unable to participate in mining.
Even at 10MB, it requires investing in a relatively high speed connection.
Thank you. This is the most clear explanation yet that explains how an increase in the maximum block size raises the minimum bandwidth requirements for mining nodes.
Given this bandwidth limitation, here's a new proposal for the adjustment of maximum block size:
1) A boolean flag is added to each block. The flag represents the block solver's yes or no vote for increasing the block size. The independent miner or mining pool sets this flag according to their preference for an increase.
2) Every time the difficulty is adjusted, the number of yes votes is counted from the last adjustment. If the number of yes votes is greater than 90%, then the block size is increased by 1%. Both percentages are baked-in constants, requiring a hard fork to change.Interesting, an intergrated voting method. I can't say which direction that I'd consider it more likely that most miners would prefer, which is a good sign that it's a viable solution. However, I don't know that I'd agree that a 1% change per difficulty adjustment is going to be enough. After all, there will only be roughly 26 such adjustments in one year. Taking into account the compounding of prior adjustments, off of the top of my head I'd guess that it's not possible for the blocksize to increase by more than 35% in one calender year. And only then if all the vote adjustments move in the same direction. I'd say a better number would be 5% per adjustment if the vote was a supermajority (i.e. 80% of votes in one direction) or 2.5% (or so) for a simple majority. This would, at least, make it
possible for the blocksize to double in a calender year, even if it doesn't make such an outcome likely.