A data transmission system, comprising: a sending node, comprising: a first link queue, configured to store data packets to be transmitted to a receiving node on a first network link (120.1); a first link-specific congestion control, associated with the first link queue, the first link-specific congestion control configured to control a first congestion window, wherein the first congestion window, controlled based on an available capacity of the first network link (120.1), determines a size of the first link queue for the data packets to be transmitted; a plurality of flow senders, configured to transmit data packets of a plurality of data flows to flow receivers on the receiving node, a plurality of flow-specific receive window controls, independent from the first link-specific congestion control, wherein exactly one flow-specific receive window control is associated with each data flow of the plurality of data flows, wherein each flow-specific receive window control is configured to control a receive window of the associated flow sender based on an available capacity of the corresponding flow receiver to specify an amount of data available to be entered into the first link queue; a second link queue configured to store data packets to be transmitted to the receiving node on a second network link (120.2); and a second link-specific congestion control, associated with the second link queue, the second link-specific congestion control configured to control a second congestion window, wherein the second congestion window, controlled based on an available capacity of the second network link (120.2), determines a size of the second link queue for the data packets to be transmitted, wherein data, made available by one of the plurality of flow senders are made available to one selected from a group consisting of the first and the second network link to the flow receivers on the receiving node, wherein the second link-specific congestion control is configured to make a first determination that the second congestion window does not allow the sending of the data, wherein the first link-specific congestion control is configured to make a second determination that the first congestion window allows the sending of the data, and wherein the first network link (120.1) is configured to allow sending at least one data packet comprising the data based on the second determination. a first link queue, configured to store data packets to be transmitted to a receiving node on a first network link (120.1); a first link-specific congestion control, associated with the first link queue, the first link-specific congestion control configured to control a first congestion window, wherein the first congestion window, controlled based on an available capacity of the first network link (120.1), determines a size of the first link queue for the data packets to be transmitted; a plurality of flow senders, configured to transmit data packets of a plurality of data flows to flow receivers on the receiving node, a plurality of flow-specific receive window controls, independent from the first link-specific congestion control, wherein exactly one flow-specific receive window control is associated with each data flow of the plurality of data flows, wherein each flow-specific receive window control is configured to control a receive window of the associated flow sender based on an available capacity of the corresponding flow receiver to specify an amount of data available to be entered into the first link queue; wherein exactly one flow-specific receive window control is associated with each data flow of the plurality of data flows, wherein each flow-specific receive window control is configured to control a receive window of the associated flow sender based on an available capacity of the corresponding flow receiver to specify an amount of data available to be entered into the first link queue; a second link queue configured to store data packets to be transmitted to the receiving node on a second network link (120.2); and a second link-specific congestion control, associated with the second link queue, the second link-specific congestion control configured to control a second congestion window, wherein the second congestion window, controlled based on an available capacity of the second network link (120.2), determines a size of the second link queue for the data packets to be transmitted, wherein data, made available by one of the plurality of flow senders are made available to one selected from a group consisting of the first and the second network link to the flow receivers on the receiving node, wherein the second link-specific congestion control is configured to make a first determination that the second congestion window does not allow the sending of the data, wherein the first link-specific congestion control is configured to make a second determination that the first congestion window allows the sending of the data, and wherein the first network link (120.1) is configured to allow sending at least one data packet comprising the data based on the second determination.