Software-defined networking is a familiar concept in the data center and the service provider marketplace. But...
the networking approach is also beginning to make inroads in other networking operations, including WLAN. Meru Networks this summer became the first WLAN vendor to get OpenFlow 1.0 conformance certification from the Open Networking Foundation for its Wi-Fi equipment. The certification is one step in a strategy that Meru is promoting to enterprises looking for ways to unify their wired switches and wireless access points via SDN.
For recognition of its efforts, Meru is this month's winner of the SearchNetworking Network Innovation Award. SearchNetworking spoke with Ajay Malik, Meru's senior vice president of worldwide engineering and products.
What compelled Meru to begin to lay the groundwork to develop an OpenFlow-certified SDN application for the wireless market?
Ajay Malik: We began researching how software-defined networking (SDN) could help enterprises have a unified view of their networks. Although most view SDN as a technology for the data center, we started to look at it from the vantage point of how SDN could help the campus and how it can help the unified wired and wireless environment.
We then began to look into OpenFlow and we said, 'OK, if we implement OpenFlow in our controllers and give it access up to our access point (AP), then what happens to the SDN controller or any application?' We would then have visibility into every infrastructure device, the wireless AP, the wireless controller, the wired switches, everything. And we could now have a unified network view by enabling OpenFlow to our controllers and access points. But that was just the tip of it.
What were some of the other advantages that you saw from this wireless SDN effort?
Malik: We also realized that it's not just the visibility. Using SDN, we can control the quality of service (QoS), so now you can write an application that is looking at the network as a host. Doing that, I can enable troubleshooting across the network; I can enable QoS across the network. I have full control of all the resources across the unified network. In fact, you do not need wired and wireless gear made by the same vendor. You can select best-of-breed wired and wireless vendors to meet the needs of your network and your organization.
What were some of the challenges you had to overcome to get the Meru platform certified?
Malik: What SDN is doing is making the network very simple. In SDN, to enable all this, what you need is an API to program all the flows -- distinguish flows based on the device type, the location, the IP address, the media access control (MAC) address, etc. The first challenge we had was that we don’t expose those programmable APIs.
Exposing those APIs was significant work. And then the second challenge we had was that we have to exist in a hybrid world -- a world that is SDN as well as non-SDN.
There is a plethora of applications -- BYOD, access management, etc.-- that were written before SDN, and those use only MAC addresses. So those applications are already there today. If you begin adding new SDN applications, both have to co-exist. We can't imagine that everyone is going to move away from old applications and move to SDN applications immediately. We implemented those APIs and modified our forwarding engines, but still ensured that our forwarding engine can handle forwarding requests happening because of non-SDN applications as well.
How did you expose the APIs?
Malik: The API is exposed via OpenFlow and sFlow – we followed the OpenFlow spec.
Characterize the certification process with OpenFlow.
Malik: We began implementing SDN last year and in April  we were ready with our first round of implementations. We then participated in the Open Networking Summit to demonstrate. At that point in time, the Open Networking Foundation (ONF) connected us with an OpenFlow conformance testing lab, Criterion Networks.
That was an interesting experience as the labs and ONF had not talked about nor had they done any wireless controller or AP certification.
What are some of the enterprise applications that you believe will be created from this effort?
Malik: When we initially started, a lot of people were saying, 'SDN is a solution looking for a problem.' But, when we began talking about use cases and the applications for the unified wired-wireless network, it resonated extremely well. We found a lot of customers buying into it, not only buying into the idea, but wanting to do a proof of concept. Let me give you one example.
One of the biggest universities we spoke to [it has a big Meru deployment] had not enabled Apple's Bonjour protocol in their dorms. It's a simple protocol, but at a university, where you have hundreds of rooms and students have thousands of devices, you can see all Bonjour devices and it becomes almost unusable. We said we could write an SDN application that would limit visibility of Bonjour flows only to the authorized users -- and we created a personal area network using SDN.
Any other examples?
Malik: Possibilities for applications are limitless -- applications for enabling predictable quality of service, visibility across the network, troubleshooting/diagnostics. People started talking to us with respect to security, access control and QoS. We were talking to a managed service provider that was having problems with its WAN links. He wanted to allow users to connect to the wireless network, even if they had a lower connectivity rate--based on how much utilization was occurring on the wired side. SDN, again, because of the holistic view, let us write an application that has visibility into how much traffic is going, and how many flows are going and based on that it can rate-limit the wireless flows.
How do you train your sales force to educate the market about the role of SDN in wireless?
Malik: It is actually easier for the sales force. It's no more a technical sale. You don’t need to talk about the technology; you can now talk about real problems around visibility, performance and control. It's easier to discuss. But yes, there is still an educational element. However, when the audience connects to the unified story, they immediately get it.
What's next for Meru? How do you expect to get wireless SDN further into the marketplace?
Malik: More applications. I think we need a solid ecosystem of application developers, customers and partners who will develop apps. I don't expect 1 million apps in the networking world like the iPhone, but we do expect quite a few apps and we believe we have built the right innovation platform to enable that.
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