58C？ o？ Me? n？ Exchange? u？ s？ d？ t？ The trading mechanism of perpetual contract imitates the structure of commodity futures trading, but it is different from commodity futures. ? u？ s？ d？ t？ The basic price of a permanent contract is some head exchange indexes, and all the margin and profit and loss are based on? u？ s？ d？ t？ Pricing. ? u？ s？ d？ t？ Is it a perpetual contract and the whole process with digital currency as the subject matter? u？ s？ d？ t？ Digital currency contract for pricing and settlement, referred to as "? u？ s？ d？ t？ Contract ".