TED: Inter-domain traffic engineering via deflection

As inter-domain routing on today's Internet does not and basically cannot consider traffic load when determining best traffic forwarding paths, it is not always optimal for a router to forward packets along its default path, especially when the router's default output port incurs a long queuing delay. In this paper, we design a new approach called TED in which border routers of autonomous systems (AS) adaptively deflect outbound traffic from a congested default path to an alternative path to significantly improve inter-domain traffic engineering (TE) and end-to-end throughput. With TED, every router only needs to examine the queue length of its own outgoing ports to orchestrate its deflection operation and ensure traffic forwarding is at line speed. It does not need to communicate or coordinate with other TED-capable routers or modify packet content, making TED incrementally deployable. Our evaluation shows that TED significantly increases the average throughput of traffic flows, and the improvement is comparable to directly upgrading router hardware and capacity. Finally, a prototype of TED on NetFPGA is also implemented.