Nobody is willing to just hand you some free cash in return for nothing, especially not a business. Using modern ASICs from Bitfury they make sure that they are really using as efficient and powerful hardware as possible. Bitcoin cloud mining, sometimes called cloud hashing, enables users to buy the output of Bitcoin mining power from Bitcoin mining hardware placed in remote data centres. The major factor that is unknown to both parties is the Bitcoin network difficulty and it drastically determines the profitability of the bitcoin cloud hashing contracts. The Bitcoin network has a global block difficulty.