Elastic Edge-Overlay Methods Using OpenFlow for Cloud Networks

The virtualization of cloud network requires flexible and effective techniques to accommodate the rapid changes in the network configurations and updates. OpenFlow protocol has attracted attentions for cloud networks since it facilitates managing and sharing the network resources, and it can be utilized to create an overlay abstraction on top of the network infrastructure for the flow setup in the cloud. However, the traditional reactive flow setup of OpenFlow introduces higher flow latency and overhead on the network controller. This paper discusses the issues of the reactive flow setup and presents two optimized overlay network virtualization methods that leverage OpenFlow to control and forward the tenants’ traffic. The proposed methods enable tenants to use their own MAC/IP addresses in the cloud. We have implemented and evaluated the proposed overlay methods, and the experimental results show that our methods have less flow latency than the traditional reactive approach, and higher performance than the popular overlay tunneling protocols such as VXLAN, STT, and NVGRE.