Thank you, and my apologies. I should have sent that link just to you and not put everyone on cc. On Fri, Sep 14, 2018 at 1:30 PM Andrew wrote: > (reposting to whole list instead of just him) @Moral Agent: > Interesting proposal though it introduces some elements > of proof of stake so it would be more controversial in my view. Also, > something needs to be explained about how this would not create an > attack where difficulty is frequently dropping by 25%, and suddenly we > find ourselves with a very low difficulty and PoW attacks can easily > happen. I need to analyse your proposal more, but I prefer to discuss > it on your blog instead of here just to limit the side topics and > focus only on my proposal. > > No one has yet given me a good reason for why not to support my proposal... > > On Fri, Sep 14, 2018 at 2:49 PM, Moral Agent > wrote: > > You might be interested in an idea I wrote about that is in a similar > spirit > > here: > > > > > https://medium.com/coinmonks/taming-large-miners-with-helper-blocks-6ae67ac242f6 > > > > From the article: > > > > When a block is solved, it randomly selects one satoshi from the utxo set > > and gives whomever controls that satoshi the power to generate a “Helper > > Block”. The Helper Block commits to a subset of transactions for > inclusion > > in the next block. A miner can accept the Helper Block by including the > > suggested transactions and giving the associated transaction fees to a > > payment address specified in the Helper Block. Miners who do not use a > > Helper Block must satisfy a 25% higher difficulty. > > > > On Fri, Sep 14, 2018 at 9:56 AM Andrew via bitcoin-dev > > wrote: > >> > >> I discussed this more at bitcointalk: > >> https://bitcointalk.org/index.php?topic=4998410.0 > >> > >> The attacks I'm interested in preventing are not only selfish mining > >> and collusion, but also more subtle attacks like block withholding, > >> and in general anything that aims to drive out the competition in > >> order to increase hashrate fraction. I also scrapped the idea of > >> changing the block subsidies, and I am only focuses on fees. > >> > >> You can read more about the motivation and details in the bitcointalk > >> thread, but my proposal in short would be to add the concept of > >> "reserve fees". When a user makes a transaction, for each txout > >> script, they can add parameters that specify the fraction of the total > >> fee that is held in "reserve" and the time it is held in "reserve" > >> (can set a limit of 2016 blocks). This "reserve" part of the fee will > >> be paid to miners if the hashrate rises. So if hashrate is currently h > >> and peak hashrate (from past year) is p, then for each period (1 day), > >> a new hashrate is calculated h1, and if h1 > h, then the fraction > >> (h1-h)/p from the reserve fees created in the past 2016 blocks will be > >> released to miners for that period (spread out over the 144 blocks in > >> that period). And this will keep happening as long as hashrate keeps > >> rising, until the "contract" expires, and the leftover part can be > >> used by the owner of the unspent output, but it can only be used for > >> paying fees, not as inputs for future transactions (to save on block > >> space). > >> > >> This should incentivize miners to not drive out the competition, since > >> if they do, there will be less of these reserve fees given to miners. > >> Yes in the end the miners will get all the fees, but with rising > >> hashrate they get an unconditional subsidy that does not require > >> transactions, thus more space for transactions with fees. > >> > >> I can make a formal BIP and pull request, but I need to know if there > >> is interest in this. Now fees don't play such a large part of the > >> block reward, but they will get more important, and this change > >> wouldn't force anything (would be voluntary by each user), just miners > >> have to agree to it with a soft fork (so they don't spend from the > >> anyone-can-spend outputs used for reserve fees). Resource requirements > >> for validation are quite small I believe. > >> > >> On Sat, Sep 1, 2018 at 12:11 AM, Andrew wrote: > >> > As I understand, selfish mining is an attack where miners collude to > >> > mine at a lower hashrate then with all miners working independently. > >> > What are the current strategies used to prevent this and what are the > >> > future plans? > >> > > >> > One idea I have is to let the block reward get "modulated" according > >> > to peak hashrate. Say p is the peak hashrate for 365 periods (1 year) > >> > consisting of 144 blocks, h is the hashrate of the last 144 block (1 > >> > day) period, and r is the base subsidy (12.5 BTC currently). You can > >> > then make the max block reward 0.5 r (1 + h/p). So if hashrate is at > >> > peak you get the full reward. Otherwise you get less, down to a min of > >> > 0.5 r. > >> > > >> > If miners were to collude to mine at a lower than peak hashrate, then > >> > they may be able to do it profitably for 144 blocks, but after that, > >> > the reward would get modulated and it wouldn't be so much in their > >> > interest to continue mining at the lower hashrate. > >> > > >> > What flaws are there with this? I know it could be controversial due > >> > to easier mining present for early miners, so maybe it would have to > >> > be done in combination with a new more dynamic difficulty adjustment > >> > algorithm. But I don't see how hashrate can continue rising > >> > indefinitely, so a solution should be made for selfish mining. > >> > > >> > Also when subsidies stop and a fee market is needed, I guess a portion > >> > of the fees can be withheld for later if hashrate is not at peak. > >> > > >> > > >> > -- > >> > PGP: B6AC 822C 451D 6304 6A28 49E9 7DB7 011C D53B 5647 > >> > >> > >> > >> -- > >> PGP: B6AC 822C 451D 6304 6A28 49E9 7DB7 011C D53B 5647 > >> _______________________________________________ > >> bitcoin-dev mailing list > >> bitcoin-dev@lists.linuxfoundation.org > >> https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev > > > > -- > PGP: B6AC 822C 451D 6304 6A28 49E9 7DB7 011C D53B 5647 >