Meanwhile, a subsystem referred to as "Chengxintong" runs to furnish security for every trading as a third party and guarantees the online payment safety.

But attention is neither a currency nor a commodity. It can, to some extent, be bought and sold. But it cannot be traded to third parties, and it is not entirely fungible.

Traditional water right trading between different users may bring third-party effects as reducing the instream flow of the intermediate stream and downstream.