A communication system for transmitting a Transmission Control Protocol, TCP, segment over a communication network using a Multipath Transmission Control Protocol, MPTCP, the communication system comprising a communication device, a further communication device and a network entity, wherein the communication device comprises: - a communication interface configured to establish an MPTCP data flow comprising a plurality of data sub-flows to the further communication device, wherein the plurality of data sub-flows is combined for capacity aggregation, and - a scheduler configured to select, for the TCP segment, a data sub-flow from the plurality of data sub-flows, wherein the communication interface is further configured to transmit the TCP segment via the data sub-flow selected by the scheduler to the further communication device, the network entity is configured to determine, for each of the plurality of sub-flows, at least one priority indicator indicating a respective priority of a respective data sub-flow, the network entity comprises: - a processor configured to determine a plurality of cost parameters of the plurality of data sub-flows, wherein each cost parameter indicates a cost of a respective data sub-flow, to determine a plurality of priorities of the plurality of data sub-flows based on the plurality of cost parameters, and to generate the at least one priority indicator based on the plurality of priorities, and - a communication interface configured to transmit the at least one priority indicator for a respective sub-flow to the communication device, wherein: a.) the communication interface of the communication device is configured to receive at least one priority indicator from a network entity, wherein the at least one priority indicator indicates a respective priority of a respective data sub-flow, b.) the scheduler of the communication device is configured to determine a data sub-flow with the highest priority from the plurality of data sub-flows and, if exists, a sub-group of the plurality of data sub-flows, wherein each data sub-flow within the sub-group has the highest priority, c.) the scheduler of the communication device is configured to determine at least one latency indicator indicating a respective latency of a respective data sub-flow, and d.) the scheduler of the communication device is further configured to select the data sub-flow for the TCP segment from the plurality of data sub-flows, based on the at least one priority indicator as a primary criterion and based on the at least one latency indicator as a secondary criterion, by selecting, for the TCP segment, the data sub-flow having the highest priority, but if, however, there are at least two data sub-flows with the same highest priority, the data sub-flow having the lowest latency within that sub-group of data sub-flows with the same priority. - a communication interface configured to establish an MPTCP data flow comprising a plurality of data sub-flows to the further communication device, wherein the plurality of data sub-flows is combined for capacity aggregation, and - a scheduler configured to select, for the TCP segment, a data sub-flow from the plurality of data sub-flows, wherein the communication interface is further configured to transmit the TCP segment via the data sub-flow selected by the scheduler to the further communication device, the network entity is configured to determine, for each of the plurality of sub-flows, at least one priority indicator indicating a respective priority of a respective data sub-flow, - a processor configured to determine a plurality of cost parameters of the plurality of data sub-flows, wherein each cost parameter indicates a cost of a respective data sub-flow, to determine a plurality of priorities of the plurality of data sub-flows based on the plurality of cost parameters, and to generate the at least one priority indicator based on the plurality of priorities, and - a communication interface configured to transmit the at least one priority indicator for a respective sub-flow to the communication device, a.) the communication interface of the communication device is configured to receive at least one priority indicator from a network entity, wherein the at least one priority indicator indicates a respective priority of a respective data sub-flow, b.) the scheduler of the communication device is configured to determine a data sub-flow with the highest priority from the plurality of data sub-flows and, if exists, a sub-group of the plurality of data sub-flows, wherein each data sub-flow within the sub-group has the highest priority, c.) the scheduler of the communication device is configured to determine at least one latency indicator indicating a respective latency of a respective data sub-flow, and d.) the scheduler of the communication device is further configured to select the data sub-flow for the TCP segment from the plurality of data sub-flows, based on the at least one priority indicator as a primary criterion and based on the at least one latency indicator as a secondary criterion, by selecting, for the TCP segment, the data sub-flow having the highest priority, but if, however, there are at least two data sub-flows with the same highest priority, the data sub-flow having the lowest latency within that sub-group of data sub-flows with the same priority.