ELI5 for BIP100?

[achow101]

There is a historical limit of 32 Mb on Bitcoin message sizes, thus also limiting blocks since blocks are passed in the block p2p message.

Miners vote for block sizes within the range of half of the current to double the current block size (e.g if the block size is 1 mb, then miners can vote to change the block size to somewhere between 0.5 mb and 2 mb. They cannot go below 0 or greater than 32 mb whatsoever. The hard fork is scheduled to occur after 90% of the last 12000 blocks support BIP 100 and the date is past Jan 11 2016. Presumably (the bip is unclear on when the votes are counted) the block size limit is also changed every 12000 blocks. Miners vote by encoding ‘BV’+BlockSizeRequestValue into the coinbase script to vote for their block size limit. The final size is determined by dropping the highest 20% and lowest 20% votes and then choosing the minimum (the bip is not very clear on what is actually chosen).

If he said that, he is really bad at math.
If you drop the lowest 20% and take the minimum, it doesn't matter if you also drop the highest 20%, since the minimum stays the same

That is what I understood from the pdf, but I could be wrong. Someone on the mailing list did ask him for clarification on this but he did not respond yet.

[CryptoEdge]

i guess you are right, it cant pass 32 MB.

Not only that. It gives all voting right to pool operators. End users have no right to exercise. Size of mempool needs to be considered. My vote goes for this proposal.

Dynamic Blocksize makes alot of sense. It should be made to scale dynamically as adoption and growth scale organically.

[achow101]

There was a reply by Garzik to the question about how the votes are counted. The block size chosen is the 20th percentile block, meaning that the supposed 21% attack cannot work. This means that it will choose the block size which is greater than 20% of the all of the other votes. Even if a miner had 21% of the mining power, they cannot change or force a minimum since all of their blocks would not be in the 20th percentile, they would probably be in the 1st or 2nd percentile.

[Finksy]

Anyone else notice the size of the last block?

974.74 kb  & 2,320 transactions.

https://blockchain.info/block/00000000000000000971eaf8d7ad55052ae8a109f2e723a77dec911c0cadb850

[HostFat]

With BIP100 it is possible to arrive to 32 MB in 12 months

[meono]

i guess you are right, it cant pass 32 MB.

Not only that. It gives all voting right to pool operators. End users have no right to exercise. Size of mempool needs to be considered. My vote goes for this proposal.

Dynamic Blocksize makes alot of sense. It should be made to scale dynamically as adoption and growth scale organically.

I disagree the dynamic blocksize limit does not make any sense whatsoever. Remember we're talking about limit not the blocksize.

If we have parameters that determizr the blocksize limit then we should not have limit at all. We're governing the wrong target.