Light Reading
Why it's time to bring clarity to the SDN controller northbound interface debate.

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
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
Operators should leverage their network, QoS, billing and big data to compete against OTT players with both consumer and enterprise offers.
Is it smarter to centralize network intelligence for LTE-Advanced and 5G, or continue the Flat-IP 4G trend of pushing intelligence to the edge?
Is your network built on 'The Old IP,' or are you part of 'The New IP' revolution?
Carriers are being left out of purchases made on mobile phones, but they have the opportunity to get back in the value chain for both physical and virtual buys.
The Internet of Things (IoT) will provide a major challenge for network operators, but SDN and NFV can help.
Flash Poll
LRTV Huawei Video Resource Center
Sales Director of INIT on Plug & Play Switch Devices

9|19|14   |   3:21   |   (0) comments


INIT Italy uses both the Huawei S5700 and S7700 series switches for the campus LAN environment. Sales Director Andrea Curti says their company chose these Huawei devices over others because of their performance, flexible scalability and plug-and-play features.
LRTV Huawei Video Resource Center
Saudi Arabia Upgrades Vocational Training System

9|19|14   |   3:31   |   (0) comments


The Technical and Vocational Training Corporation (TVTC) has 100,000 students, 150 government-owned institutions and oversees 1000 private institutes. The CIO of TVTC explains that Huawei devices have allowed them to manage multiple datacenters using just one software program, scientifically tracking the progress of students and teachers, saving them millions.
LRTV Huawei Video Resource Center
Huawei's Media Solutions Are Here to Stay

9|19|14   |   4:35   |   (0) comments


The current media revolution requires rapid upgrades in technology. New formats (HD, 3D, 4K etc.) and the subsequent explosion of file sizes demand sophisticated network and storage architecture. Social media and the multiple distribution channels require a robust asset management system. Gartner analyst Venecia Liu speaks about the current technological trends in ...
LRTV Huawei Video Resource Center
Microgenesis on Huawei's Switches

9|19|14   |   3:57   |   (0) comments


Microgenesis is a solutions and system integrator company in the Philippines whose areas of expertise include data centers, networking and security products. In this video, Executive Director Jeffrey Choa talks to us about his customers needs and they benefit from using Huawei switches.
LRTV Huawei Video Resource Center
Network Solutions Help the Philippines Jump Ahead

9|17|14   |   2:59   |   (0) comments


In the past, the Philippines has under-invested in technology. Now, the CEO of Softshell talks about how Huawei products help the Philippines jump ahead as the economy improves.
LRTV Huawei Video Resource Center
VCS Observation for Safer Cities in the Netherlands

9|17|14   |   5:20   |   (0) comments


Holland's VCS Observation has been operating for 22 years. Its main goal is to get cities safer. CEO Wim van Deijzen tells us some of the challenges his company faces and how Huawei is helping to overcome these challenges.
LRTV Huawei Video Resource Center
A Conversation With Serbia's Ministry of Interior

9|17|14   |   4:38   |   (0) comments


At HCC 2014, the Assistant Minister of the Ministry of Interior of the Republic of Serbia talks to us about his projects and corporation with Huawei. Solutions like Safe City and E-Government and services like cloud computing are just some of the areas his department is interested in.
LRTV Huawei Video Resource Center
IHS Analyst Discusses eLTE at CCW 2014

9|10|14   |   7:09   |   (0) comments


Thomas Lynch, associate director of critical communications at IHS Technology, talks about broadband in critical communications.
LRTV Huawei Video Resource Center
TCAA on Huawei eLTE: A Broadband Solution for Mission-Critical Communications

9|10|14   |   2:29   |   (0) comments


At CCW2014 in Singapore, the TCCA's Phil Kidner talks about the importance of broadband data for critical communications.
LRTV Custom TV
Spotlight on Cisco: SDN for Optical Networks

9|8|14   |   9:27   |   (0) comments


Cisco's Greg Nehib talks OpenFlow and more on the 'Software-Defined Networking for Optical Networks' panel at the Big Telecom Event in June 2014.
LRTV Custom TV
Cisco's Evolved Programmable Network (EPN)

9|8|14   |   4:05   |   (0) comments


A look at the various demos Cisco showed at Light Reading's Big Telecom Event highlighting Cisco's EPN innovation and how SDN and NFV technologies are enabling a variety of new services.
LRTV Huawei Video Resource Center
The Future of Ultra-Broadband, With Kevin Kelly (UBBF2014)

9|5|14   |   1:13   |   (1) comment


If you think the technological changes we've seen up to now are astounding, just wait until you see what the future has in store. Discuss upcoming breakthroughs with Kevin Kelly, Founding Executive Editor of Wired Magazine, at the Huawei Ultra-Broadband Forum on September 24.
Upcoming Live Events!!
September 23, 2014, Denver, CO
October 29, 2014, New York City
November 6, 2014, Santa Clara
November 11, 2014, Atlanta, GA
December 2, 2014, New York City
December 3, 2014, New York City
December 9-10, 2014, Reykjavik, Iceland
June 9-10, 2015, Chicago, IL
Infographics
A survey conducted by Vasona Networks suggests that 72% of mobile users expect good performance all the time, and they'll blame the network operator when it's not up to par.
Today's Cartoon
Vacation Special Caption Competition Click Here
Latest Comment
Hot Topics
AT&T: We'll Bundle Fixed Wireless & DirecTV
Mari Silbey, Independent Technology Editor, 9/15/2014
New NFV Forum Focused on Interoperability
Carol Wilson, Editor-at-large, 9/16/2014
NFV & The Data Center: Top 10 Takeaways
Sarah Reedy, Senior Editor, 9/18/2014
Connecticut Cities Crowdsource Gigabit Nets
Jason Meyers, Senior Editor, Utility Communications/IoT, 9/15/2014
Pics: LR's Women in Telecom Breakfast
Sarah Reedy, Senior Editor, 9/16/2014
Like Us on Facebook
Twitter Feed