An Improved Blockchain Consensus Protocol with Distributed Verifiable Delay Function

The difficulty adjustment algorithm (DAA) embeded in a proof of work (PoW)-based blockchain often causes a fluctuation on the block generation, which results in either no blocks for a long time or many blocks for a short time. In addition, this strategy also leads to potential attacks on the DAA (such as jumping mining attack, selfish attack, etc.). To solve these problems, we propose an improved blockchain consensus protocol which utilizes the PoW with a distributed verifiable delay function (DVDF). Our protocol can retain the proof of work mechanism to ensure that the probability of finding a suitable block. Also, With the DVDF, our protocol can ensure that all the miners perform a calculation that requires a relatively fixed time despite his/her considerable hashrate. Consequently, the fluctuation of the hashrate of the blockchain caused by the DAA can be dismissed by our scheme. Eventually, our improved consensus protocol can resist the attacks caused by this weakness. Finally, simulation experiments are proposed to support our improvements.