Annulus: A Dual Congestion Control Loop for Datacenter and WAN Traffic Aggregates

This video is of the talk presenting Annulus, a dual congestion control loop scheme for datacenter and WAN traffic aggregates. \r\n\r\nCloud services are deployed in datacenters connected though high-bandwidth Wide Area Networks (WANs). The talk describes our findings related to the interaction between WAN and datacenter traffic, explaining why this interaction can cause performance impairments for both types of traffic. This behavior is caused by the long round-trip time (RTT) for WAN traffic, combined with limited buffering in datacenter switches. \r\n\r\nAnnulus addresses these problems through its two control loops. The first control loop leverages existing congestion control algorithms for bottlenecks where there is only one type of traffic (i.e., WAN or datacenter). The other loop handles bottlenecks shared between WAN and datacenter traffic near the traffic source, using direct feedback from the bottleneck. The talk presents some of the results evaluating Annulus on a testbed.