Blocksize attack vector possible now?

[arnoudk]

Hi all,

I'm wondering if there is an attack vector on the blockchain that is possible now, because of the block size limit being (nearly) reached.

Imagine if just one single large miner decided to mine only empty blocks. Bitcoin is based on the assumption that the majority of miners are honest - and in this case it does not need to be a majority.

They would be able to limit the total transaction throughput (withholding attack) - not only their own. In a system that is not at capacity (or has no capacity limit), the next miner will simply include the transactions that the first miner excluded, thank the first miner for the extra transaction fees, and no harm is done. But, in a system that is at capacity, the miners have to work together to process transactions and resolve backlogs as quickly as humanly possible.

Miners should not have to work together! They should compete fiercely. In my humble opinion, it should not matter how any one actor chooses to behave.

The community should, in my opinion, speak out more loudly against those who are blocking bitcoin's growth. They are threatening the user experience (long confirmations). They are threatening the explicit assumptions that form the basis of the bitcoin ecosystem.

Don't ask the core devs that do not want to understand this to change. They have no power, except what we - the community - give them. Instead, DEMAND that miners use the power they have to protect the system. The power is with the people, the miners are just their servants.

[ERt1F2Wvyr]

Consensus on increasing the block size has now finally been reached. Although to address your point if the amount of transactions overfills the blocks and keeps continuing to do so for long enough. Then I'm led to believe that it could bring down the whole network. That is what the transaction fee is for to make it too expensive to run a sustained spam attack on the network too long. Although a balance is needed to be found to have as low as transaction fee as practically possible. To help enable and foster more decentralised micro-payments.