Fujitsu Network Communications, the U.S.-based subsidiary of Japanese giant Fujitsu, has created a software-defined networking (SDN) architecture based on OpenDaylight that creates abstraction at both the infrastructure layer and at the application layer.

Optical networking is an expertise of Fujitsu Network Communications, so naturally, its SDN architecture — named Virtuora NC, with a 3.0 version that was launched last week — reaches down to the transport layer.

Igor Bergman, VP of Fujitsu Network Communications' software business unit, says abstraction means different things for the southbound interface and the northbound interface.

For the southbound, Fujitsu has created a device driver, using the YANG modeling language and XML, to collect information from network elements in the optical layer, no matter which vendor manufactured the devices.

“The controller itself loses the awareness of the manufacturer,” says Bergman. “The controller talks to the model, instead of the devices themselves. It gives the opportunity to be multivendor.”

Using abstraction for the southbound layer, it becomes much faster to support new devices, whether from Cisco, Juniper, Alcatel-Lucent, or another manufacturer. Bergman estimates it takes about two weeks.

The modeling data is stored in OpenDaylight's model-driven service abstraction layer (MD-SAL). Fujitsu is also working on an ONOS version of the controller.

On the northbound side, MD-SAL gets information from the model and talks to multiple applications on top of the controller.

Bergman says the innovation in Virtuora NC 3.0 is that it uses open source software based on OpenDaylight but not necessarily locked into OpenDaylight; it allows devices from multiple vendors; and it manages services across Layers 0-3. He says the architecture allows flexibility of commands all the way from the northbound to the southbound.

“The problem with most controllers today is they are Layer 2-3,” he says. “They are missing the transport component, which is critical to service providers.”