Let’s forget about all of this recent SDN washing and go back to virtual networking basics. Most of us by now know what a software switch is. It is also known as a vswitch or virtual switch. This is arguably the most critical piece of real estate in the next generation data center network. So, who owns this property?
I’ve noticed recently within the Enterprise space there is a lack of awareness around Open vSwitch, but at the same time it is extremely popular in the large scale cloud environments. It is because of this I was motivated to write this post.
The Open vSwitch is an open source virtual switch equivalent to those from Cisco and VMware in that it runs in the kernel on the hypervisor. OVS is the default virtual switch in Xen Server 6.0 and Xen Cloud Platform. It is also supported in KVM, Virtual Box, and other Linux environments making it a very versatile platform. On top of that, something very special about OVS is that it supports the OpenFlow protocol. Open source switch and OpenFlow may just be a win-win for those out there looking at inexpensive ways to start testing SDN applications. All you need is an open source controller to get started such as Floodlight or Nox.
Even more interesting is that start-up Nicira, who was recently acquired by VMware for $1.2B, was leading the development of Open vSwitch. We still don’t know how this will play out, but one can speculate to see full and native OVS support in a future release of vSphere giving VMware more flexibility in virtual network deployments.
Looking at other Software Defined Networking startups such as Big Switch and Midokura, we can see they are also leveraging Open vSwitch in their virtual network deployments. While Big Switch is not aligned to any particular virtual switch per se, they are leveraging the Open vSwitch because it does support the OpenFlow protocol they are actively promoting. Midokura uses OVS as well, but like Nicira is believed to have done, Midokura has added some additional software to make their magic work.
After all, it is an *open* switch. It is as open as you view it though. Even though it’s open, deploying open solutions with proprietary extensions makes it closed if you ask me. Does that really matter? That’s your call. What’s more important is that the solutions are solving the needs of customer environments.
I do in fact think there is room for value added hardware in the world of software defined networking (SDN), but the bottom line is, the main control will happen in the new access layer.
As you explore SDN controllers and virtual network services, a question to think about is, can any given vswitch be used for a particular controller or virtual network appliance, or are the options limited, or maybe the question should be, should the network services and applications be picked first prior to the vswitch being selected? What about the hypervisor? Are there compatibility issues?
Ultimately, the answer is that the data center needs to be thought about holistically to extract the most value from it. Otherwise, we’ll just remain silo’d operating at far less than maximum efficiency. After all, what business really strives for that?
Welcome to the beginning of the future.
Jason
Follow me on Twitter: @jedelman8
PS - After I wrote this, I actually went digging for articles on OVS and found some really good ones. Check out these two by Matthew Palmer and Brad Casemore. They give much more insight into how this will impact open networking in the data center. My post is meant to simply bring awareness to the Open vSwitch project. It is funny how Matthew chose to use “Battle Ground” and I used “War Zone.” Battle Ground makes more sense when looking at the data center overall, but these network companies have to admit they are declaring war on each other :). As usual, we’ll have to see how it plays out over time!