Polkadex uses nominated Proof of Stake (NPoS) as its consensus mechanism. The coins used in the polkadex ecosystem are called PDEX tokens. While staking, one can choose to become either a nominator or a validator. As a nominator, one can nominate trusted validators such as RadiumBlock and earn PDEX tokens as reward. Validators produce new blocks by validating transactions in the chain.
The role of a validator in the ecosystem is crucial. Each transaction has to be carefully approved as approval of spurious transactions will have serious repercussions like loss of credibility and as well as a part of their stake.
Nominators may nominate upto 16 validators as trusted candidates. Both validators and nominators can stake their tokens as collateral and receive rewards.