Abstract
Software-defined networking (SDN) has demonstrated tremendous potential for altering the networking landscape in both academia and
industry. While traffic engineering as network intelligence in classic technologies have received considerable attention from the research
community, traffic engineering in the SDN space, particularly in regards to quality of service (QoS), remains relatively unexplored.
While recent efforts have begun to show how SDN might be leverage to meet the complex traffic-shaping needs of modern networks, there is still much that can be done to illustrate its potential, and in particular how it could prevent degradation of service for all QoS
traffic. We propose methods to allow other flows to use bandwidth unused by high-priority transfers, while ensuring that bandwidth
assigned to those high-priority transfers is available when needed. We present fine-tuned control over bandwidth allocation that achieves an efficient combination of both the differentiated service (DiffServ)-style classification and the integrated service (IntServ)-style perflow
considerations. We also show how this method may be used over a wide area network (WAN) to optimally adjust bandwidth allocations when high-priority data transfers are not using their allocated bandwidth.
