A New Blockchain Proposal Supporting Multi-Stage Proof-of-Work

We introduce a new variant of decentralised, trustless, permissionless blockchain. The main novelty is that the proof-of-work for mining a block is divided into multiple stages. An appropriate linkage structure is defined so that it becomes possible to simultaneously work on various stages of different blocks. The overall effect is an improvement in the transaction processing rate and the time for confirming a transaction. These are achieved without compromising on security. The division of the proof-of-work into several stages also divides the block reward into an equal number of stage rewards. Once a block gets onto the blockchain, the miner which successfully completed a particular stage can claim the reward for that stage. This ensures a more equitable distribution of the reward for successfully mining a block

Spy Based Analysis of Selfish Mining Attack on Multi-Stage Blockchain

In this paper, we present a selfish mining attack on the multi-stage blockchain proposed by Palash Sarkar. We provide detailed analysis of computational wastage of honest miners and biased rewards achieved by the selfish pool. In our analysis, we introduce a spy inside an honest pool which is a trivial task. Our spy is responsible for leaking the information of the stage mining from the honest pool to the selfish pool. In our analysis, we consider all the possible configurations of mining namely sequential, parallel and pipelining. In all of these configurations, we show through our mathematical equations as to how a selfish miner can succeed in wasting the computation power of the honest miner and how he can influence the reward of mining. For completeness, we provide an algorithm for performing a selfish mining attack on all the scenarios on multi-stage blockchain. To thwart selfish mining on multi-stage blockchain we redesign the original verification algorithm by introducing a new parameter called the crypto-stamp. We present a new algorithm that uses crypto-stamp during the verification process of the mined stages or blocks and is able to detect with high probability whether the stages or blocks were kept private or not