The IoTeX Mainnet utilizes the Roll-DPoS consensus mechanism, a more democratic version of delegated proof of stake (DPoS) with high throughput, instant finality and high resilience to network attacks. Fundamentally different from proof of work (PoW) and proof of stake (PoS) mechanisms, Roll-DPoS allows for massive scalability while maintaining high decentralization. In Roll-DPoS, token holders take into account several factors, such as HW/SW resources, tokens stake, network contributions, and reputation, when voting for Delegates. Delegates are rank-ordered by the number of votes they receive, and the top vote-getters are deemed “Consensus Delegates” for the current epoch — this is what we call the “ranking scheme”. From the pool of Consensus Delegates, a sub-committee is randomly selected by a randomization algorithm to maintain consensus and produce new blocks for every new epoch. After being selected to the sub-committee, the primary role of a Consensus Delegate is to produce/verify blocks and are rewarded in IOTX tokens . For more details, please see our Roll-DPoS yellow paper and high-level video overview.