STTR Phase II: Increased Security for Blockchains Applied to Healthcare

The broader impact/commercial potential of this Small Business Technology Transfer (STTR) Phase II project is a significant increase to the security of healthcare safe public-private blockchain protocols. The use of blockchain technology drives efficiencies in direct alignment with improved patient experience and improved health, both at a reduced cost. The economic impact of bringing down the costs of providing healthcare has the potential to benefit millions of lives. One serious threat on Proof-of-Work (PoW) blockchains is the double-spend attack. With a successful double-spend attack, miners can reverse payments and obscure the audit trail of data access. The deployment of the proposed protocol will ensure the integrity of both these properties. More broadly, the proposed system can improve security for any PoW blockchain, such as Bitcoin, Ethereum, and Litecoin. The system can also greatly improve user experience by processing in a timely and standard manner via regularly created blocks. This STTR Phase II project proposes to virtually remove the threat of double-spends for healthcare safe blockchains. Existing PoW blockchains are based on computational puzzles. Once a miner solves a puzzle, she adds a block to the chain and is rewarded with coins. In expectation, miners produce blocks proportional to their share of the computational resources. But mining is a random process and occasionally a miner with a small share of the resources can generate a majority of the blocks. In those cases, a minority miner can overwrite existing blocks, nullifying or double-spending earlier entries. The proposed system prevents double-spend attacks by requiring miners to aggregate multiple solutions to the PoW problem before submitting a block. This aggregation ensures that miners with the majority of the processing power have a high probability of submitting the majority of the blocks, reducing the risk of double-spends by orders of magnitude. The technical work includes: First, developing a new consensus mechanism for blockchains. The consensus mechanism is a highly sensitive, embedded piece of software and this adoption will be handled with careful engineering. Second, the project will decrease associated bandwidth use on the network, a primary cost. The project will seek to create a new solution for reducing network costs based on advanced filters. Third, the project will address and mitigate remaining security issues, such as proof withholding attacks and Denial of Service attacks. Finally, the work will empirically quantify the improvements to ensure high quality engineering and to inform translation strategy. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.