“…Following a similar approach as in [16], we carried out a qualitative comparison between our proposed protocol and the following proof-based consensus protocols: Pure PoW [38], Cuckoo hash function-based PoW [39], Prime number finding-based PoW [23], Double puzzles-based PoW [40], Non-outsourceable puzzles [41], Bitcoin-NG [42], GHOST strategy [43], Generalized PoW [44], Pure PoS (Nextcoin) [45], State of the block-based PoS [19], PoS by coin flipping from many nodes [46], Delegated PoS [47], Coin age-based PoW difficulty re-designation (Ppcoin) [20], Stake-based PoW difficulty re-designation (Blackcoin) [21], Coin age with an exponential decay function [48], Combining PoW and PoS to append blocks sequentially [49], with difficulty adjustment [50], Proof of activity [51], Puzzles designed for human PoW [22], Proof of burn [24], Proof of space [25], Proof of elapsed time [52], Proof of luck [53], Multichain [54]; and the following Vote-based consensus protocols: Hyperledger with practical Byzantine fault tolerance [55], Symbiont, R3 Corda with BFT-SMaRt [56,57], Iroha with Sumeragi [58,59], Ripple [60], Stellar [61], Quorum with Raft [62], Chain [63].…”