SDNs Promise to Simplify Network Management in the Data Center

Networking in the data center can be complicated to manage. It’s not only expensive, but any configuration error can have a cascading impact across the entire data center.

The good news is that, after living with this issue for more than three decades, something is finally being done about it. Networking vendors are developing software defined networking (SDN) architectures that allow IT organizations to manage networks at a much higher-level abstraction. These new architectures will not only reduce the total cost of managing networks in the enterprise, but could virtually eliminate the opportunity to introduce configuration errors into the system.

At the core of most of those efforts is OpenFlow, a set of standards that allows a remote controller to modify the behavior of any networking device via a common set of instructions. Arguably long overdue, OpenFlow is an industry response to the demand for ways to introduce higher levels of automation into the data center. In turn, that’s sparked off a race between Cisco, Hewlett-Packard, IBM, and Extreme Networks to leverage OpenFlow and other technologies to deliver next-generation networking gear based on SDN architectures.

IBM officials argue that their company, which acquired Blade Network Technologies in 2010, doesn’t get enough credit for building one of the first switches to support OpenFlow. Now IBM is extending SDN technology into new offerings such as its recently introduced PureSystems, which bring server, storage and networking resources together within a common management framework.

But it was HP that really kick-started the OpenFlow conversation with its launch of a Virtual Application Networking (VAN) offering. The core component of an HP VAN is an HP Intelligent Management Center (IMC) VAN Manager Module that creates a set of templates, which include predetermined parameters and policies for configuring and managing HP networking gear. HP has also made available an HP VAN Manager VMware Plug-in that simplifies management of VMware virtual machines, as well as HP IMC Extended APIs that provide an extensible Web services platform for integrating custom enterprise applications with the HP IMC platform.

Cisco responded shortly thereafter with the Cisco Open Network Environment, which is anchored around a software development kit, dubbed OnePlatform Kit (onePK), that is essentially a set of application programming interfaces that make it easier to access router and switch functionality at a much higher level of abstraction. According to Prashant Gandhi, senior director of product management in the Cisco Server Access and Virtualization Group, Cisco fully intends to support OpenFlow—which, at least for the moment, it views as a more “experimental” technology. In the meantime, Cisco is using onePK to make its investments in SDN technologies, in order to help reduce the network complexity more accessible to developers.

Extreme Networks, right on the heels of Cisco, outlined its own SDN strategy for OpenFlow, which initially makes networking gear from Extreme Networks manageable via controllers from NEC and BigSwitch using the Quantum APIs defined under the emerging OpenFlow standard.

Not to be outdone, other networking vendors such as Juniper Networks and Brocade have signaled their intentions to support OpenFlow, while vendors such as ADARA Networks are taking a software-only approach to building SDNs that span multi-vendor networks.

While SDNs and OpenFlow are clearly still an emerging technology, the implications for the data center are profound. Once it becomes easier to manage networks at a higher level of abstraction, it will be much easier to service and support multi-vendor networks. That means IT organizations will have the capability to more realistically play one networking vendor off another, without having to concede the fact that actually deploying networking equipment from multiple vendors actually increases their total costs of ownership (TCO).

Longer term, OpenFlow will also give developers more granular control over network services accessible via a standard set of APIs. “OpenFlow is really about creating a programmable control plane for the network layer,” said Shehzad Merchant, vice president of technology for Extreme Networks.

To achieve that goal, investments in SDN technologies have begun to rapidly expand, most notably in the formation of an Open Networking Research Center led by Stanford University and the University of California at Berkeley. In fact, by 2016 IDC is forecasting that the SDN market will be worth about $2 billion.

Mike Matchett, a senior analyst with Taneja Group, suggests there will be multiple approaches to SDNs, ranging from individual networking vendors developing for their own equipment to cross-platform approaches that manage networking equipment from multiple vendors.

“The thing they will all have in common is that you’ll be able to define the network through software to manage all the components as though they were one logical network,” he said. “But it’s not like one SDN approach is likely to dominate, so organizations will find themselves coping with multiple types of SDN technologies, especially across multiple data centers.”


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