Is a consensus where validation occurs through signing blocks with a wallet (or delegated key of the wallet) on which a definite sum of tokens is blocked. Unlike [[Proof of Work (PoW)]], PoS doesn't depend on hash algorithms. To confirm ownership of funds (coins or tokens) digital signature is used. Every participant has a chance to be randomly chosen as new [[Block]] creator (validator) and this chance can be increased proportionally by increasing the "weight" of the node (it's shared in the total pool of locked [[Token Delegated (m-token)|m-tokens]]). In this case consensus is something like lottery. Reward is calculated in coins. Proof of Service is a part of node verification based on [[Proof of Stake (PoS)]] before engaging in the network. It is an additional condition to PoS, which shows that node provides some service.