Estimation of End-to-End Available Bandwidth and Link Capacity in SDN

Abstract

The traditional networks, with the control and data plane integrated into the same network devices, do not provide a global view of the network performance like degree of congestion, bandwidth utilization, etc. Software defined network (SDN) is an approach towards this problem which separates the control plane of the switch from its data plane and provide a centralized control plane so as to get a global view of the network performance and thus make decisions of how to regulate flows. In SDN, network monitoring can be achieved more efficiently than traditional networks using OpenFlow statistics. SDN controller can keep track of available bandwidth on each link and thus estimate end-to-end available bandwidth of a path simply by composing individual link bandwidths thus avoiding end-to-end probing. We have made two contributions in this paper: (i) proposed and validated a method to estimate end-to-end available bandwidth on any given path by composing link-wise available bandwidths (ii) proposed a method to measure link capacity using OpenFlow protocol. We compared our results to the ones obtained using the state-of-the-art bandwidth measurement tool, Yaz