DomainFlow: practical flow management method using multiple flow tables in commodity switches

A scalable network with high bisection bandwidth and high availability requires efficient use of the multiple paths between pairs of end hosts. OpenFlow is an innovative technology and enables fine-grained, flow level control of Ethernet switching. However, the flow table structure defined by OpenFlow is not hardware friendly and the scalability is limited by the switch device. OpenFlow is also not sufficient for fast multipath failover. To overcome these limitations, we propose DomainFlow in which the network is split into sections and exact matches are used where possible to enable practical flow management using OpenFlow for commodity switches. We applied a prototype of DomainFlow to multipath flow management in the Virtual eXtensible LAN (VXLAN) overlay network environment. The total number of flow entries was reduced to 1/128 using currently available commodity switches, which was not possible before.