Explicit Rate Flow Control in Metro Ethernet Networks

In this paper, we first studied the performance of IEEE 802.3x flow control and its enhanced scheme, the DiffPause [1]. We found that such on-off flow control is not able to quickly react to the network bandwidth fluctuation and may result in buffer overflow and packet drop. Moreover, the flow control performance deteriorates with the larger transmission delay, which is typical in the Metro Ethernet that has long transmission distance. To overcome above problems, we proposed an Explicit Ethernet Rate Control (EERC) algorithm based on control theory. Our simulation shows that the EERC flow control greatly improves the response time and reduces the chance of overflow or underflow.