Network operators are deploying Software Defined Networks (SDN) to enable programmability of their networks for efficiency, speed of deployment and new revenue-generating network services.  Widespread adoption of the programmability paradigm depends on the availability of common or standardized APIs that allow access to domain specific attributes and mechanisms without requiring the API itself to be specific to the vendor or technology. The Transport API (T-API) is designed to allow network operators to deploy SDN across a multi-domain, multi-vendor transport infrastructure, extending programmability across their networks end-to-end.

By working through the specifications, rigorous interoperability testing and validation, OIF has substantiated T-API as the Northbound Interface (NBI) of choice. OIF, in collaboration with industry leaders, has helped establish a foundation for open, programmable networks that allow operators to efficiently deliver dynamic multi-domain connectivity services to the market.

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Assuring Open Optical Networking Interoperability

Press Releases



  • Optinet China 2021 – Beijing – “Overview of OIF Transport SDN Projects
    Wednesday, June 16, 2021 – 11:50-12:10 China Standard Time
    During this session, an OIF expert will discuss OIF’s Transport SDN projects and the 2020 Transport SDN API Interop Demonstration, where operator-defined use cases and deployment scenarios for multi-vendor Layer 0 and Layer 1 networks were tested in the Telefonica Madrid lab using the ONF T-API 2.1.3 and OpenConfig device APIs for interoperability between devices, SDN controllers and orchestrators.
    Presenter: Hu Qian, OIF Representative, Senior Engineer, Optical Communication Research Center of China Telecom Beijing Research Institute
  • OFC 2019 March 7, 2019 at 11:15am
    OIF Panel on Showfloor: “The Path to Open, Interoperable Optical Networking
    Moderator: Dave Brown, OIF Communications Director, Nokia
  • NGON & DCI World 2019 – May 21, 2019 at 8:00am
    The Optical Masterclass Series – Optical Internetworking Forum (OIF) Panelists: Dave Brown, Nokia and OIF Director of Communications and Karl Gass, OIF Physical & Link Layer Working Group Vice Chair, Optical
  • OFC 2018
  • Optinet China 2018
  • SDN NFV World Congress

Success Story

Fact Sheet

For more information on this project contact Jonathan Sadler, Networking Interoperability Working Group Chair (acting) at

For information on other OIF current projects, please see OIF Current Work

For public OIF Implementation Agreements, please see Implementation Agreements (IAs)