Evaluation of delay performance in valiant load-balancing network

Network traffic grows in an unpredictable way, which forces network operators to over-provision their backbone network in order to meet the increasing demands. In the consideration of new users, applications and unexpected failures, the utilization is typically below 30% [1]. There are two methods aimed to solve this problem. The first one is to adjust link capacity with the variation of traffic. However in optical network, rapid signaling scheme and large buffer is required. The second method is to use the statistical multiplexing function of IP routers connected point-to-point by optical links to counteract the effect brought by traffic's variation [2]. But the routing mechanism would be much more complex, and introduce more overheads into backbone network. To exert the potential of network and reduce its overhead, the use of Valiant Load-balancing for backbone network has been proposed in order to enhance the utilization of the network and to simplify the routing process. Raising the network utilization and improving throughput would inevitably influence the end-to-end delay. However, the study on delays of Load-balancing is lack. In the work presented in this paper, we study the delay performance in Valiant Load-balancing network, and isolate the queuing delay for modeling and detail analysis. We design the architecture of a switch with the ability of load-balancing for our simulation and experiment, and analyze the relationship between switch architecture and delay performance.