Quote from: Infinum on August 31, 2013, 04:26:28 PM

As a full blockchain node operator I really want to see some kind of solution to the blockchain bloat problem, preferably with some fees so I can turn this into a business rather than a non-profit. Miners verify transactions and get compensation for it, but nobody pays for the transaction's storage once it gets verified and this will eventually shrink full-nodes numbers and further strengthen the oligopoly of Bitcoin miners.

The advantage of storage is that you can verify more transactions. However, that is not much good if other miners drop your block because they dropped the UTXO.

The only "market" solutions are something like UTXO "rental" or just add a hard limit for the rate at which the set can increase per block.

Rental could be implemented by having a system where unspent UTXOs are dropped from memory after a while. Each block a UTXO could have its output drop by . Once it drops below zero, it is dropped from the in memory set. This wouldn't actually cause the output to be less valuable, as long as you spent it before it was dropped it would be ok. Spending old transactions would require adding info for fast loading. For example, the tx message would have to also include info to allow fast proving that the UTXO is valid.

This is something that have a merkle tree for the UTXO set would be helpful for. You give the path to prove the UTXO is valid and then it doesn't need to be contained in memory.