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Enterprise Strategy Group Sheds Insight on Nexus 1000V Virtual Network Overlays

ESGThe Enterprise Strategy Group (ESG) has released this week a whitepaper and companion video looking at virtual network overlays and their use in multi-tenant environments. This comes on the heels of the ESG research brief on Cisco’s recently announced Cisco ONE set of network programming interfaces which includes Nexus 1000V-based virtual overlays.

ESG points out that virtual network overlays are important to building out multi-tenant environments like private and hybrid clouds, as well as overcoming scalability issues in those environments that have traditionally been based on VLANs. As ESG notes, and as Cisco mentioned in it’s ONE announcement, programmability of the virtual networks is what really separates them from classic overlays based on MPLS or GRE tunnels. The Nexus 1000V will achieve this programmability capability by SDN API’s such as OpenStack on top of the Nexus 1000V virtual supervisor module.

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SDN for Universities: Campus Slicing 101

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.

Campus Slicing diagramUniversity 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.

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Some Afterthoughts on Open Network Environment, SDN and Overlay Networks

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.

Open Network EnvironmentIn 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 »

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Cisco live! Recap: Jimmy Ray Talks Virtual Overlays and “Programming” the Network

This week at Cisco live! in San Diego I had a chance to catch up with Jimmy Ray Purser and talk about Cisco’s strategy for programming the network, and specifically programming virtual network slices of a larger physical infrastructure:

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Nexus 1000V and Virtual Network Overlays Play Pivotal Role in Software Defined Networks

There’s an incredible amount of hype and excitement these days around Software Defined Networking (SDN), which promises to herald in a new age of flexibility, business agility and automation to our existing data center and campus networks. Since there are very few, if any, SDN networks in production environments today, though, we know there are a lot of implementation details to work out before the industry achieves the lofty benefits of network programmability. Cisco opened its kimono this week on its strategy around programmable networks (an even broader concept than what we believe the traditional definition of SDN is), called Cisco Open Network Environment. (Get Omar’s take on Cisco ONE).

Open Network EnvironmentIf you are like a lot of people, you might think that SDN is synonymous with OpenFlow, the leading standards-based approach for SDN today. However, we are already seeing folks across the industry extending the SDN vision beyond what OpenFlow is currently envisioned to do, so we think the definition of SDN will probably evolve over the next year or so to include additional programming models and protocols. Cisco ONE, for example, includes three approaches to network programmability: 1) our own onePK set of API’s to Cisco network operation systems and devices, 2) a portfolio of agents and controllers that will support OpenFlow, among other things, and 3) our Nexus 1000V-based portfolio for building virtual network overlays.

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