Optical transport networks can be supported by OpenFlow in an ONF Optical Transport Working Group (OTWG) architecture. OpenFlow in data centers supports layer 2 to layer 4 networks, but support for multilayer layer 0 to layer 4 networks where OpenFlow acts as the unified interface is possible with OpenFlow covering the circuit (layer 0 and layer 4) network.

In traditional multilayer networks, every packet and optical network has its administrator, database, and network management system (NMS). In such networks, design and operation are implemented on the network individually. Changes in such a network require a long chain of discussion that can last up to weeks between the administrators to achieve this. Future operation of multilayer networks that implement an SDN/OpenFlow architecture have the resources (packet and optical) abstracted to be processes in the unified database.

Implementation of such a model has multiple advantages, such as rapid service creation, where resources needed by the optical network can be allocated in a shorter period when required by the packet network, and capital expenditure and operation expenditure costs are reduced drastically. The following diagrams give a pictorial explanation of a unified database versus the current multilayer networks: