L2OVX: An On-demand VPLS Service with Software-Defined Networks

Virtual Private LAN Service (VPLS) is a widely used network technology which connects geographically distributed customer sites as a local area network. However, the process of provisioning a new VPLS circuit is complicated because service provider has to check device configurations one by one. Therefore, it is difficult to provide the service on demand. OpenFlow, the most notable protocol in Software Defined Networking (SDN), manage the network devices via a well-defined set of instructions and exposes the handling capability of flows to a centralized controller. By this logically centralized programmatic model, we have a consistent and convenient way to dynamically allocate an end-to-end path for a VPLS service. In this paper, we present a system L2OVX which leverages OpenVirteX, a network virtualization platform, to realize the VPLS service on-demand in SDN. This solution provides layer 2 translation to achieve virtualization process with line-rate performance, and enables the load balance function to improve the transfer bandwidth among tenants. The result of evaluation shows L2OVX is competitive with OpenVirteX according to the TCP throughput on software-based OpenFlow switches and moreover, supports most hardware OpenFlow-enabled switches to provide the line-rate throughput. Furthermore, for scalability, the number of flow entries for one tenant remains constant in L2OVX while grows exponentially in OpenVirteX.