& cplSiteName &

Compass Check: ONF & the Northbound API(s)

Dan Pitt
Column
Dan Pitt
11/6/2013
50%
50%

The Open Networking Foundation (ONF) turned a lot of heads in October with the announcement of a Northbound Interfaces (NBI) Working Group.

While we're always glad to draw more attention to the benefits of Software-Defined Networking (SDN), we want to be sure that the industry truly understands why we are looking north and how this new Working Group fits into the overall focus of Open Networking Foundation (ONF). This is especially important since we have been so vocal for more than two years about why we are not standardizing the northbound API. (Believe me, I've taken a lot of flak for that, but steadfastly resisted.)

ONF's mission is to accelerate the adoption of open SDN. To us, SDN includes both the OpenFlow substrate and the enablement of applications and services above it. This means that while our NBI Working Group is new, our work with the Northbound Interface is not.

Back in June 2011, we received an inquiry from another industry group asking if we planned to standardize the Northbound API. "Goodness, no," we replied, but we neglected to say why.

"Oh good," they replied. "Then we will."

Damage control included explaining why no one should, because:

  • No one had enough experience with OpenFlow controllers to know what to standardize
  • This period of innovative experimentation was important for learning and we did not want to stifle it
  • Anyone who tried would surely get it wrong
  • There won't be just one NBI anyway, and
  • That's not how software artifacts get standardized.

Fortunately, they listened.

Since then, the industry has built a considerable body of experience. With a solid OpenFlow substrate, the attention now shifts to include the software and services that the foundation enables. We have seen a greater demand from developers of application, orchestration, and management software for assistance in understanding NBIs as a critical component of a complete SDN solution.

So in the fall of 2012 we began looking at NBIs in the form of the Architecture and Framework Working Group's study of existing SDN use cases and controller interfaces, which are many. The large number of unique controller APIs indicates that there is no consensus yet on what makes the right NBI (and could also lead one to believe that they are not that hard to write). We will soon publish the first edition of our NBI study, cataloguing and comparing them.

While this proliferation of SDN controllers brings some valuable learning, it also creates confusion for those wanting to write to an NBI. Without stable interfaces to write to, overall adoption of SDN slows, and when we heard concerns from many in the ONF user population, we knew that we had to take action.

The question then became: What action should the ONF take? We have long said that software APIs are not typically standardized in advance by committees, because they don't have to be. Anyone can modify an (open) interface quickly; it's not like redesigning an ASIC. What we as an organization can do is bring clarity to the choices and their benefits, through both investigation and prototyping.

Therefore, ONF took the leap and chartered the NBI Working Group, which is evaluating Northbound Interfaces. Plural. That's an important distinction. The Working Group has already put together a chart showing how broad the topic is. Characterizing the different levels of abstraction as latitudes and the different use cases as longitudes, they starkly demonstrate the futility of imagining there being one, or "the," NBI.

Our first step will be to develop information models for Northbound Interfaces at different latitudes and longitudes with plans to prototype and gain market feedback on select examples. Again, examples -- plural.

What we don't plan to do is rush to a standard. ONF has spoken passionately about standards, and we have committed to standardizing only what is truly necessary. If the industry needs us to help them arrive at a standard for some use case, we will. Prominent among our members' requirements are for the interfaces they write to to be truly open and not vulnerable to the whims of a single vendor. Moreover, we suspect that a small number of NBIs will serve a large fraction of current market needs. Thus, one of the purposes of our NBI Working Group will be to determine if an NBI standard from a committee is needed by the market at this time.

ONF plans to publish its Northbound Interface information models in 2014, accompanied by open-source working code for select use cases. We will also continue to strengthen the OpenFlow substrate to make sure it offers great service to the software and services above the NBI.

As always, user needs remain our only compass.

— Dan Pitt, Executive Director, Open Networking Foundation

(1)  | 
Comment  | 
Print  | 
Newest First  |  Oldest First  |  Threaded View        ADD A COMMENT
sam masud
50%
50%
sam masud,
User Rank: Light Sabre
11/6/2013 | 2:33:21 PM
So what now?.
Dan,

Although it makes a lot of sense to have standard NBIs, I'm wondering whether having ONF standardize on the NBIs might slow the down the adoption of SDN. Also, curious as to what you would advise a customer who's considering deploying SDN--should they wait on the ONF's NBIs or go with whatever solutions are out there?

 
More Blogs from Column
Mobile edge computing (MEC) and a cloud-native core are necessary ingredients for the future 5G NFV network, argues Ian Maclean of Metaswitch.
Once pay-TV providers embrace the idea, they must take a comprehensive, company-wide approach to carry out such fundamental changes.
5G will require a fresh look at RF characteristics as operators deploy next-gen tech on very high-band frequencies.
MVPDs have an opportunity to make digital investments without upending their current business.
VoLTE, in the end, becomes a cloud and NFV story, Metaswitch's Ian Maclean argues.
Featured Video
From The Founder
The 'gleaming city on a hill,' Steve Saunders calls it. But who is going to take us from today's NFV componentry to the grand future of a self-driving network? Here's a look at the vendors hoping to make it happen.
Flash Poll
Upcoming Live Events
September 28, 2017, Denver, CO
October 18, 2017, Colorado Convention Center - Denver, CO
November 1, 2017, The Royal Garden Hotel
November 1, 2017, The Montcalm Marble Arch
November 2, 2017, 8 Northumberland Avenue, London, UK
November 10, 2017, The Westin Times Square, New York, NY
November 30, 2017, The Westin Times Square
All Upcoming Live Events
Infographics
With the mobile ecosystem becoming increasingly vulnerable to security threats, AdaptiveMobile has laid out some of the key considerations for the wireless community.
Hot Topics
Could the Connected Car Help Prevent Terrorism?
Dan Jones, Mobile Editor, 9/15/2017
Cities Slam FCC on Broadband Proceedings
Mari Silbey, Senior Editor, Cable/Video, 9/15/2017
Could 5G Have Found Its Glass Ceiling?
Dan Jones, Mobile Editor, 9/20/2017
Apple's New iPhones: No Gigabit LTE for You!
Dan Jones, Mobile Editor, 9/14/2017
1 Million Pirate Set-Top Boxes Sold in the UK
Aditya Kishore, Practice Leader, Video Transformation, Telco Transformation, 9/20/2017
Animals with Phones
Live Digital Audio

Understanding the full experience of women in technology requires starting at the collegiate level (or sooner) and studying the technologies women are involved with, company cultures they're part of and personal experiences of individuals.

During this WiC radio show, we will talk with Nicole Engelbert, the director of Research & Analysis for Ovum Technology and a 23-year telecom industry veteran, about her experiences and perspectives on women in tech. Engelbert covers infrastructure, applications and industries for Ovum, but she is also involved in the research firm's higher education team and has helped colleges and universities globally leverage technology as a strategy for improving recruitment, retention and graduation performance.

She will share her unique insight into the collegiate level, where women pursuing engineering and STEM-related degrees is dwindling. Engelbert will also reveal new, original Ovum research on the topics of artificial intelligence, the Internet of Things, security and augmented reality, as well as discuss what each of those technologies might mean for women in our field. As always, we'll also leave plenty of time to answer all your questions live on the air and chat board.

Like Us on Facebook
Twitter Feed