Traffic Engineering of High-Rate Large-Sized Flows

High-rate large-sized (alpha) flows have adverse effects on delay-sensitive flows. Research-and-education network providers are interested in identifying such flows within their networks, and directing these flows to traffic-engineered QoS-controlled virtual circuits. To achieve this goal, a design is proposed for a hybrid network traffic engineering system (HNTES) that would run on an external server, gather NetFlow reports from routers, analyze these reports to identify alpha-flow source/destination address prefixes, configure firewall filter rules at ingress routers to extract future flows and redirect them to previously provisioned intra-domain virtual circuits. T his paper presents an evaluation of this HNTES design using NetFlow reports collected over a 7-month period from four ESnet routers. Our analysis shows that had HNTES been deployed, it would have been highly effective, e. g., > 90% of alpha-bytes that arrived at the four routers over the 7-month period would have been redirected to virtual circuits. Design aspects such as whether to use /24 subnet IDs or /32 addresses in firewall filters, and which router interfaces' NetFlow reports to include in the HNTES analysis, are studied.