Experiences Implementing QoS Aware Routing on Off-the-shelf SDN Switches

This paper provides an overview of the Quality of Service (QoS) capabilities defined in the OpenFlow specification. Several vendor documentations from off-the-shelf products are compared with the OpenFlow specification. This research reveals inconsistencies between the specification and the vendors implementation. Queues for examples are not implemented by all vendors. This gap can lead to interoperability problems in a network while using hardware from different vendors. The research also shows, that the majority of vendors provide a port statistic function which gives information about incoming and outgoing bandwidth about each port of a switch. Based on this function a QoS aware routing application for off-the-shelf switches is proposed. This concept can be used to change the flow of traffic in an OpenFlow network based on the utilization of the interfaces. Based on the conducted research, the application can be used with hardware from multiple vendors. This paper does not contain a quantitative evaluation of the implemented application.