A method, processor and system for controlling packet flow in a network provides for selecting a transmission scheme based on a payload rate for payloads arriving at a buffer. The transmission scheme includes data blocks comprising packets each having an associated payload, the data blocks have a variable packet transmission rate and a variable payload per packet ratio. The product of the variable packet transmission rate and the variable payload per packet ratio remains constant. The data blocks are sent to a network switch that deterministically routes the data blocks.