WEBridge: west-east bridge for distributed heterogeneous SDN NOSes peering

Large networks are often partitioned by the network operators into several smaller networks when deploying software-defined networks SDNs. Additionally, a dedicated network operating system NOS is deployed for each of these SDNs. Each NOS can learn the local network view that enables control of how data packets are forwarded within its network. Controlling the flow of data packets in an entire network requires each NOS to have a global network view to determine the next NOS hop. Hence, NOSes are required to share or exchange reachability and topological information. How such information is efficiently exchanged has not been well addressed so far, especially in the case of multi-vendor NOSes. This paper proposes a west-east bridge mechanism for distributed heterogeneous NOSes to cooperate in enterprise/data center/intra-autonomous system networks. We propose to simplify physical networks into virtual networks and only exchange the simplified virtual network information to construct the global network view. To achieve a resilient peer-to-peer control plane of distributed heterogeneous NOSes, we propose a "maximum connection degree"-based connection algorithm. Considering the security issue, we adopt controller identity authentication. We implement the west-east bridge and analyze the performance obtained: about 100% of enterprises and data centers, and about 99.5% of autonomous systems can adopt to this solution. The deployment in three SDNs CERNET, Internet2, and CSTNET proves the feasibility. Copyright © 2014 John Wiley & Sons, Ltd.