Bitcoin: Securing the Network

This white paper investigates how the Bitcoin network will be sustained, especially as its incentive structure changes in coming years.In the coming decades the mining incentive structure of the Bitcoin network is set to shift from block rewards to transaction fees. For this transition to be effective, the network needs to remain robust enough to prevent a 51% attack, while continuing to facilitate transactions at a low cost. Once block rewards phase out, ARK Invest’s research demonstrates that a transaction fee of 1.2% would be sufficient to incentivize the buildout of a network that is secure from an economically profitable 51% attack, regardless of bitcoin’s market cap and the capital allocation of a nefarious miner. This 1.2% fee would underpin other potential transactions in the Bitcoin network beyond the bitcoin currency, which could include real estate transfers, venture capital contracts, and machine-to-machine transmissions.