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SDN 101: What It Is, Why It Matters, and How to Do It

Despite all the buzz about software-defined networking (SDN), many organizations don’t yet have a clear idea of how it will benefit them. In this blog, I’ll tackle the what and why of SDN, and explain the different approaches you can consider.

What: A Disruptive Approach to Network Control

For the last quarter century, network devices have performed two types of processing:

  • The data plane looks at a routing table to decide where to forward packets. This processing takes place in dedicated hardware ASICs.
  • The control plane takes care of everything else, such as spanning tree, AAA, exporting NetFlow statistics, SNMP, and more. The control plane is implemented in software, and you can think of it as the brains of the network element.

So, if your network includes 200, 2000, or 20,000 network devices, that means you’re managing 200, 2000, or 20,000 control planes and keeping all of them up to date. Read More »

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Programmability and SDN are not the same

June 26, 2013 at 7:05 am PST

Network programmability means democracy, means freedom, freedom to program across all layers and entities, software or hardware – depending on your needs. Is SDN required to have network programmability? Not at all. Does the SDN architecture leverage network programmability? Yes, of course.  So, why do many people equate network programmability and SDN? Read More »

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The “Business” of Software Defined Networking

I admit it. I’ve grown weary of the debate about whether SDN includes network programmability or whether or not SDN can only be accomplished through NfV, or the relative merits of control plane / dataplane separation. I will leave those debates to others more focused on the technology itself.  Personally, I have been more fascinated with what I see as the new business opportunities emerging around SDN.

Certainly there is a raft of opportunities for start-up companies in the controller space or in the virtualization of various networking functions. Many innovative new companies are re-examining existing network functions within the SDN paradigm; that will lead to some potentially new and useful approaches that may be cheaper/easier/faster than current designs. No doubt many customers will see value in these new ways of doing things, and everybody will benefit.

But that’s not what I find fascinating about SDN. What I am starting to see are ideas that are completely out of the box, and would likely not be thought of by typical network technologists working alone. Let me discuss a few categories of things I have seen possible with the emerging technologies.

The Network as a Compute Resource
It turns out Read More »

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Blogging Journey from Cisco Live from Cisco ONE: Intelligent Programmable Network

Cisco Live is here! It’s a great opportunity for you to discover some really exciting technology solutions at our Cisco ONE: Cisco Intelligent Programmable Network booth featuring a few of our latest innovations.

Onsite you will be able to see and ask your questions at live demos featuring applications and services developed with One Programmable Kit (onePK), Openflow and the eXtensible Network Controller. In addition, we have demos devoted to IPv6, routing, service discovery and network design simulation -- all things meant to make your network simpler and smarter.

There are also some great partner demos including our friends from SAP, Citrix, Glue Networks, Pramacom, Radware, and Starview who are showing some really cool apps that use the Cisco ONE APIs. Read More »

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Open Networking and SDN perspectives with Dr.Jim Metzler

As the hype cycle around aspects of  concepts like software-defined networking continue, customers are continuing to sift through and educate themselves to determine what is real and actionable.  I have had my fair share of participation in several events over the last 24 months,  and have been speaking to different audiences both gaining and sharing insights in the process.

One person I spoke with recently was Dr. Jim Metzler. We seem to be crossing paths at multiple venues including Interop, the Network World SDN roadshows currently underway in a few cities in the United States, as well, as at the Open Network Summit in Santa Clara a few weeks ago.

Jim has become the messiah of sorts, on some of these emerging technologies, and is frequently consulted -- both as part of his day job at Ashton, Metzler and associates and during his role hosting various industry panels on these topics. I thought it would be good to host the host and get some of his perspectives here, as we both got together at the recently held Open Networking Summit at Santa Clara.

Perpsectives on Open Networking and SDN

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