FREMONT, Calif. -- Following a 2014 prototype demonstration event, the Optical Internetworking Forum (OIF) has approved an SDN Framework whitepaper that paves the way for implementation of SDN in Carrier Networks. The whitepaper, titled “Framework for Transport SDN: Components and APIs”, documents the SDN framework for multi-domain carrier networks. It identifies critical open APIs for Transport SDN based on synthesis of the SDN layered architecture and the ITU-T ASON functional element model for optical network control.

SDN identifies interfaces separating infrastructure and control layers, and control layer from application layer. The interface between infrastructure and control layers is termed the SouthBound Interface or SBI, the interface between control and application layers is termed the NorthBound Interface or NBI, and provides APIs to the application.

“In 2014, the prototype demonstration brought together multiple vendors and carriers to test cloud-bursting services, utilizing SDN principles and interfaces,” said Lyndon Ong of Ciena and co-chair of the OIF Market Awareness & Education Committee. “The demonstration results factored into the development of a framework that allows SDN to be deployed over a carrier’s network with multiple, diverse domains.”

One of the key findings from the demonstration was that the separation introduced by the NBI and SBI enables SDN to be applied over greenfield (i.e., OpenFlow) and brownfield environments, allowing integration of domains controlled by management systems and domains using existing distributed control planes as well as centralized SDN. A variety of SBI protocols could coexist in the carrier’s Transport SDN network, including the OpenFlow protocol, with extensions for optical networks.

Optical Internetworking Forum (OIF)