What is Processing Fee, Network Fee What is the difference and who pays them?

What is Processing Fee, Network Fee What is the difference and who pays them?

Network Fee - network payment that must be paid for transaction processing by blockchain. In most cases, this variable with time and dependent on the state of a particular network parameter, in some cases it also depends on the exchange rate, for example, when transferring USDT tokens. These fees always pays the one who sends money. 
Processing Fee is cumulative fees necessary for processing and extracting money from addresses for further use of them. This collection is present in some directions, it is always charged from the balance of the Merchant and cannot be shifted to the payer directly. Typically, these fees are approximately equal to two or three (depending on the direction) Network Fee of a specific network.