I have actually bought up the question of PoW limitations in another thread on this forum.
https://bitcointalksearch.org/topic/pow-heavy-computation-is-a-feature-not-a-bug-please-critique-2976071I think first and foremost, the security of a protocol needs to be considered, a protocol is being susceptible to attacks or not is a binary measure of success. I think we can all agree the PoW is a successful protocol on that front. PoS is yet to pass these tests with different permutations of attack that are possible (long-range attacks, etc.) [I have a feeling though, like PoW, PoS will become more secure as the ecosystem grows]. Secondary reasoning needs to consider how the protocol forms emergent behavior of all players in the game.
PoS and other solutions have risen in the wake of perceived issues with PoW in secondary reasoning. The perceived issue of PoW is that the computational demand scales with the hashing power of the network and becomes labor intensive. If there is any other issue with it, please tell me, because i have not considered it yet. But looking at this point, lets make an observation of the implications PoW has to the emergent behavior of players in the ecosystem.
the hashing power provided from the network is a choice of the miners who are all playing with game theoretic like behavior. They mine for profit they obtain from mining a block. the function for block profit can be described in the following function:
netProfit BTC = (block_reward + transaction_fees) - (electricity + misc_overheads)there are two ways the block profit can scale:
- The value of BTC can increase
- The transaction fees become higher
- reduction of electricty cost via more efficient ASICS & reduction of misc_overheads
as per the bitcoin protocol, the block_reward will halve until the amount of circulating coins asymptotes to the maximum amount of possible
BTC. at which point the function is:
netProfit BTC = (transaction_fees) - (electricity + misc_overheads)As the profit they obtain from the block goes up, miners have more capability to invest and place more hashing power on the network (with the expected outcome being a higher probability that they will solve future blocks). From my observations, the miner's behavior is directly influenced by the profit of the block. Currently the bitcoin protocol is supplying the bitcoin ecosystem with
BTC (12.5 supplied as a reward per block). This increases the block profit significantly, and therefore skews the behavior of the miner to increase hashing power. This is intentional from the Bitcoin protocol because it wants to incentivize the development of the infrastructure.
When the price determination of the market set
BTC to $20,000USD, miners became more competitive to mine the block, I assume more ASIC machines were employed to provide huge amounts of hashing power (which was feasible with a
BTC price of 20k given the winner is getting
BTC12.5 + transaction fees). The large computational burden is actually a regulatory factor against the block netProfit function in a highly speculative market. The Bitcoin protocol wants steady progressive growth and development of the ecosystem and services.
So is this an issue for PoW? I would like to think, we are all here discussing this new technology because we are in it for the long run. Imagine a time when all the coins are effectively in circulation. the grossProfit would only consist of transactions_fees. This means a miner would only be able to place a feasible amount of hashing power based on the transaction_fees (this greatly simplifying the situation, but for explanation purposes, it will suffice). The transaction_fee value will be another game, played by the end users (people placing tx in the mempool).
the transaction_fee game:
choice: How much to put down as transaction fee
expected outcome: my transaction is on the next generated block
all end users playing this game will regulate the transaction_fee value with volume and demand. So this will govern the computational burden of the PoW approach. Unless I have missed something. At this point, I think PoW is working quite well in relevance to this topic.
I am up for critique on this observation. But i think we need to consider what are the reasons for saying PoW is inferior as i have seen in this thread. Its okay to say it, if we have all come to the same consensus. But until then we need to discuss it.