A network device includes a port, a buffer, a flow control module, and a service differentiation module. The port is configured to send and receive a packet, wherein the port is connected to a network entity. The buffer is configured to store the packet. The flow control module is configured to control the transmission of the packet within the network device. The service differentiation module is coupled with the buffer and the flow control module. The service differentiation module is configured to regulate storage of the packet in the buffer and to regulate the transmission of the packet from the network device to the network entity. The service differentiation module is also configured to determine excess bandwidth available within the network device and to allocate the excess bandwidth to transmit the packet to the network entity.