Flow Control for Higher Resiliency in Wide Area Distributed Cloud Computing

Wide area distributed cloud computing, where data are processed and stored at micro datacenters (DCs) located around terminals, improves response time and reduces the amount of traffic in wide area networks. However, it is difficult for the cloud to maintain service in the case of micro DC failure because the robustness of micro DCs is substantially lower than that of conventional DCs. We propose a flow control system that transfers the flow to other micro DCs by converting the L2, L3, and L4 headers of received packets via OpenFlow when micro DC failures occur. The proposed system enables flow to be transferred to other micro DCs even from M2M terminals such as sensors that are unable to change the destination IP address. We also developed a distributed control system to solve the critical problem of switching delay caused by the packet-in mechanism used when applying the OpenFlow to the distributed cloud. Emulation results showed that throughput in the distributed control became stable 12 times as quickly as that in the centralized control when flow was transferred.