Proof of Importance

Description

Gleb Kostarev:

"A final variation on these consensus mechanisms is PoI. The first cryptocurrency platform to implement this was NEM. With PoI, it is not simply coin balance that matters. NEM’s consensus system is based on the idea that productive network activity, not just the amount of coins, should be rewarded. The odds of staking a block are a function of a number of factors, including balance, reputation (determined by a separate purpose-designed system), and the number of transactions made to and from that address. This provides a more holistic picture of a ‘useful’ network member.

There are many variations on these broad approaches, and some platforms use a combination of PoW and PoS — often using the first to distribute coins, and then shifting to the second at a later point to maintain the network. Another approach is to use Masternodes in conjunction with PoW mining, as is the case with DASH and Crown. These help to process transactions and receive a share of the block rewards from miners’ activity.

In all cases, the aim of the consensus approach is to secure the network, predominantly through economic means: it should be too expensive to attack the network, and more profitable to help protect it." (https://blog.wavesplatform.com/review-of-blockchain-consensus-mechanisms-f575afae38f2)