In the wake of our Open Network Environment (Cisco ONE) announcements, we are continuing our series on software defined networking (SDN) use cases, this time focusing on the primary use case for OpenFlow and universities, campus network slicing. If interested, a more detailed solution brief on this scenario and the Cisco SDN OpenFlow controller can be found here. And check out our demo video below.
University campus networks offer an increasingly wide array of networking services to one of the broadest user bases of any “enterprise.” Some universities have medical or high-security facilities and must maintain regulatory compliance accordingly. Student networking services vary depending on whether they are on or off campus, and in almost all cases students and faculty bring their own devices. Administration offices must also be able to manage the day-to-day activities of the university. Often event management must include the rapid provisioning of point-of-sale terminal support and back-end payment reconciliation. And faculty must have both data and video access within the university campus, across campuses, and further out to other universities.
As a result, the ability to partition networks (called “slicing”) based on SDN has risen in popularity. Although slicing is being performed today on isolated networks, the need to perform it on production networks is now becoming a priority. Cisco controllers and agents, as part of the Cisco Open Network Environment for network programmability, are aimed at addressing this need.
Much of the early research and collaboration between universities on OpenFlow and SDN has been driven by the adoption of National Science Foundation (NSF) projects such as GENI, an open, collaborative research environment to explore networking at scale.
One of the basic premises of SDN is that the abstraction of control plane management, out of each network device and into a centralized “controller,” can create high business agility through automation with relatively lower OpEx and low risk. SDN is a natural fit for the class of requests universities need to service.
One of the primary components to the emergence of SDN on campuses has been the ability to create logically isolated networks and allow them to be partitioned and programmed using slicing. In SDN, this is facilitated with an abstraction layer in the network device called a flowvisor. Today, many universities use flowvisors within their isolated networks in conjunction with SDN controllers to manage their slicing requirements. In many cases these slicing activities are still performed off the campus backbone, as the software used to implement both the operating systems and slicing functions does not provide the policy management consistency required for production network applications.
After our Open Network Environment (Cisco ONE) announcement at Cisco live!, where we unveiled our strategy for network programmability, Jim Duffy at NetworkWorld had a very interesting article that asks a key question, “What are the killer apps for software defined networks?” While SDN technology is very exciting and holds a great deal of promise, the answer to that question will ultimately determine how quickly it is adopted and by who. The consensus is that network virtualization or virtual network overlays are one of the early killer apps that software defined networks can certainly enable (when coupled with other technologies), which is exactly why Cisco made virtual overlays one of the three solution pillars of its ONE announcement. As I mentioned in my TechwiseTV video on virtual overlays, the primary use case for SDN/OpenFlow research in universities is also campus network slicing or creating virtual network partitions for test and production environments, e.g., to share a physical network. As noted in Duffy’s article, virtual overlays can be done with or without OpenFlow.
In the aftermath of a major launch, after reading the press and analyst coverage of the news, I always ask what we could have made clearer, what could have been highlighted better, or how could we have made the complexity of some of the details easier to understand. One such point that probably could have been clarified is just how “open” the Open Network Environment (what’s in a name anyway?). Specifically, regarding our Nexus 1000V virtual overlay framework, there were some comments and questions about how open and interoperable this overlay framework was, especially compared to other vendors touting programmable overlays. One financial analyst firm even stated that our overlay networks had some great advantages, but only worked with Cisco switches. Read More »
For the most part, my last post was concerned about what Cisco ONE was, so explore a little more into the why. I am going to assume you read my last post, so let’s dig in. One of the fundamental concepts behind ONE is illustrated below--the idea of exposing the network in a highly granular way and emphasizing the ability to not only exert programmatic control over switch behavior, but the ability of the network to present interesting and useful information back up to the applications.
Let’s cut to the chase--you have probably wondering “what is Cisco going to do about SDN and OpenFlow?”
Well, probably more than you expect, but before we get into that, I would respectfully suggest you are asking the wrong question.
Cisco Open Network Environment (Cisco ONE) was created to deliver a specific capability to our customers: providing direct programmatic access to Cisco infrastructure. As we were vetting this concept with customers, two things quickly became apparent: 1) customers were extremely receptive to the concept and 2) there was a was wide variance in what customers were looking for. It turned out that OpenFlow and what ONF defines as SDN (in essence control plane/data plane separation) represented one approach to network programmability, but other customers were looking for to accomplish things that had nothing to do with control plane/data plane separation. For example, we see a number of universities asking for the typical OpenFlow/SDN functionality to support their R&D environments and for “network slicing”. We talked to service providers who viewed programmability as the ability to run their own code on a box--say a custom-tuned version of BGP. Finally, we talked to hyperscale data center operators who viewed programmability as the ability to get direct programatic access into the switching silicon to pull very specific and detailed information--say the port error counters--that they could fed directly into their homegrown OAM tools. At the end, it was clear we need to offer OpenFlow and SDN capabilities but we also needed to deliver more--hence the broader, more technology-agnostic concept of network programmability. So, I would offer that, instead, it might be better to ask “What is Cisco doing to make the network more programmable?”
The answer is, with Cisco ONE, quite a bit, actually. At its essence, Cisco ONE allows you to build upon the things that already work with your network (scale, availability, security, etc) and add the programmability you need to help you deal with things like cloud. mobility, etc with more agile infrastructure, simpler operations and application awareness.