Ink Protocol is a decentralized reputation and payment protocol powered by the Ethereum blockchain and XNK, an ERC20 compatible token.XNK is the underlying currency used in all Ink Protocol transactions. As a result, all transactions and feedback are backed by proof of payment on the blockchain.XNK is also earned by mediators for the mediation services that they provide on transactions.XNK is already used on the Listia marketplace as the primary virtual currency for all transactions.