A Survey on Congestion Notification Algorithm in Data Centers

days, due to fast exploitation of modern data center networks (DCNs), Ethernet is most prominently used than the conventional storage networking technologies like Fiber Channel and Infiniband. Low-loss, low-delay operations are key aspect of these conventional technologies that make them suitable for datacenter. Accordingly IEEE 802.1 standards committee is developing new specification for congestion management for Ethernet in datacenter networks. Backward Congestion Notification (BCN), Forward Explicit Congestion Notification (FECN), Enhanced Forward Explicit Congestion Notification (E-FECN), Quantizes Congestion Notification (QCN), Approximate Fair Quantizes Congestion Notification (AF-QCN) and Fair Quantizes Congestion Notification (F- QCN) is six proposals. Each of the proposals has its own advantages and disadvantages. In this paper, we provide a comprehensive survey of the most recent research activities in DCNs, with emphasis on the network congestion notification algorithms. We present a brief overview of the congestion problem along with previously proposed solutions.