Used on Polymesh, nominated proof-of-stake is a class of PoS which defines how node operators are allowed to participate in the chain’s consensus protocol and validate new blocks. It consists of two main actors: stakers (users who stake on node operators) and node operators (entities permissioned to run validator nodes). NPoS keeps the chain highly secure since it only permits node operators with the highest amounts of stake to validate blocks. This makes it harder for a single adversary to attack the chain since it takes considerable reputation to build up stake. It also makes attacking the system costly since such behavior results in stake being slashed.