Proactive Ethernet Congestion Control based on link utilization estimation

Abstract

In the quest of providing a deterministic backplane-like behaviour a mechanism called ECCP (Ethernet Congestion Control & Prevention) was proposed where specialized and expensive devices were replaced by commodity Ethernet switches while still keeping the router properties, e.g. low-latency packet delivery, no packet loss within the fabric and fair share of the bandwidth. However, ECCP uses a self-induced congestion probing model which can cause queue length fluctuation in addition to the network bandwidth wastage due to the probes. Therefore, we propose enhancements to the algorithm used by ECCP to reduce probe packet overhead. In our solution NoP-ECCP (ECCP with no probes), we use a link utilization estimation technique instead of the estimation of the available bandwidth. The results obtained through simulations show that NoP-ECCP outperforms ECCP in terms of fairness, link utilization and queue length.