Date Added: Jul 2011
In the current Internet, traffic is routed at the level of destination prefixes. The next-generation Internet requires control of traffic at the level of flows or flow aggregates. To accommodate fine-grained control, modern switching substrates (e.g., OpenFlow) maintain forwarding information for each active flow in a flow table. A separate control plane manages flows within a sub-network by updating this flow information within switches. When using network virtualization, a technique that allows sharing of networking resources among different logical networks, the physical switch and its flow table need to be shared. Current virtualization solutions in OpenFlow do not support hardware isolation in the flow table and thus lead to hidden conflicts and mis-configuration of flows.