Random idea that I got on the way home.
What about this scheme:
1. PoW functions are submitted to the network and stay in a "pool" until their "gas" has been entirely used.
By "gas" do you just mean ELC? Or do you envisage a second spendable commodity?
2. There are two types of transactions: the send-ELC transaction and the submit-work transaction.
OK. Eventually I think we will end up with many different types of transaction.
The latter is used by the "miners" to submit their proof-of-works and their bounty-solvings.
The submit-work transactions in this context spend the "gas" to the miner's address and at the same time provide the PoW proof which is verified as part of the transaction verification.
We need to distinguish between proof-of-work and proof-of-correctness. Blockchain security requires PoW. It doesn't care whether the worker is submitting correct results, so long as he has appropriately spun his wheels. The buyer, on the other hand, wants to be sure that the results are correct, including negative results. While he has the same interest in blockchain security as every other honest user,
n this context, the buyer doesn't really care how the worker obtained the results. A faster algorithm just means that he gets his results faster. (This does not mean that the FAA is benign to the buyer, since in many attack scenarios the buyer gets incorrect results.)
Proof of work is measured in the same way as discussed: With the FAA attackable SHA256 scheme. However, in this context it makes no sense for the attacker to mine his own blocks and so earn his own money.
I don't see how. If PoW (rather than some other scheme) is still being used to secure the blockchain, then an attacker might use the FAA to control the consensus.
3. This is not a consensus yet. We still need to define when a "block" is found and the chance to find it must be proportional to the work that has been done so far (so, to the number of submit-work transactions)
Here, I suggest using a "proof of stake" scheme which goes like this (and that is the trick here): The likelihood of finding a block does not increase with the ELC one holds (as in a traditional proof of stake) but with the number of submit-work transactions one has contributed to the current block.
I have an even simpler idea. Why not just have pure proof-of-stake but with no reward at all (or pehaps just the tiny transaction fees) for the PoS miner.
Without a reward, the perverse incentives criticised in the white paper and the website are eliminated. But the work will still be done. Coinholders have a strong interest in maintaining the blockchain - their coin is worthless if they don't. Additionally many coinholders will also be participants in the market, and so have an additional interest in its smooth operation.
With pure PoS, the FAA is
mostly dead. My gut feel is that it will rear its ugly head again in proof-of-correctness, but even then, in the greatly attenuated form of DoS attacks. As far as blockchain security is concerned, it's dead.