Some embodiments provide a distributed control system for controlling managed switching elements of a network. The distributed control system comprises a first network virtualizer for converting a first set of input logical forwarding plane data to a first set of output physical control plane data. It also includes a second network virtualizer for converting a second set of input logical forwarding plane data to a second set of output physical control plane data. In some embodiments, the physical control plane data is translated into physical forwarding behaviors that direct the forwarding of data by the managed switching elements.