Congestion Management for Lossless Ethernet Operation

IEEE 802.1 standards committee is working on a new specification for congestion notification in Ethernet networks. The goal of this work is to enable applications of Ethernet in backend data center networks. Such applications typically use Fiber Channel and Infiniband due to their loss-free characteristics. In this paper, an explicit rate control framework called Forward Explicit Rate Advertising (FERA) for Ethernet applications, especially data centers, is described. The framework guarantees zero packet drops at the congested switches and fast convergence to fair and stable state. In order to manage the congestion, design choices on 2-point and 3-point architectures, the reactive and proactive signaling, explicit and implicit rate controls are compared.