You will have almost certainly heard of software-defined networking (SDN) by now; it’s been the next big thing in the technology industry for a while. But what stage of its evolution are we really at, and when will the hype turn to reality?
Software-defined networking (SDN) is the separation of control plane and the hardware layer in a networking infrastructure. The intelligence is moved from the switches to a centralised controller, resulting in a far more efficient and flexible network.
It’s easy to see why the industry is pushing this as the future of networking. Moving the network intelligence to a centralised control panel means network resources can be provisioned much faster than with a traditional network setup and, because this results in networking hardware becoming a commodity, operational costs can be lower.
Some analysts and industry experts have described SDN as a “market correction” – a development that was both necessary and inevitable. While other parts of the datacentre can use virtualisation technologies to, for example, provision servers at break-neck speed, the networking element was still slowing things down. With SDN, that’s no longer the case.
But while the hype around SDN has been ongoing for a number of years now, the reality is less clear. Gartner’s famed Hype Cycle for Emerging Technologies for 2014 puts “software-defined anything” in the Innovation Trigger category. This means that while the hype may be huge, “often no usable products exist and commercial viability is unproven”.
SDN a growing IT priority
Research carried out by Computer Weekly and TechTarget has consistently shown that SDN was not high on the agenda of many IT departments across Europe. The 2014 IT Priorities Survey revealed that just 9% of businesses were considering deploying SDN over the following 12 months, a figure that hadn’t risen at all since the same survey in 2013.
One potential reason for that is that the technology is not yet living up to hype it’s receiving. “To work effectively, SDN needs two things: a means of communication between the control plane and the data plane, and a set of globally enforceable policies,” says Richard Blanford, managing director of IT integrator Fordway.
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“However, we are still some way from achieving this. At present, switches are still very proprietary, and I do not see any credible new vendors which are ready for the enterprise market.”
That’s a point of view that Brian Levy, European CTO of networking firm Brocade, generally agrees with, but says it’s more a question of relevancy and understanding rather than a lack of maturity.
“Service providers understand the value proposition, they understand what problem they are trying to solve and that is the first stage of adoption,” he says. “But then as you go down the enterprise market there is less understanding of SDN, and that’s really down to SDN being less relevant to their business.”
“It’s definitely the case that the service provider market is where the early adoption is, along with larger enterprises. And we are working towards moving SDN down into the rest of the enterprise market,” Levy adds.
Dan Pitt, executive director of the Open Networking Foundation, a group of networking suppliers committed to developing standards for SDN, says adoption is growing.
“We are seeing real-world implementations and deployments by early adopters among both telecoms service providers and enterprises, especially SMEs [small to medium-sized enterprises],” he says.
“These deployments are helping to further illustrate the benefits of SDN to a broader spectrum of users. Because of this, we expect to see increasingly mainstream SDN adoption this year that will result in additional creative SDN use cases and overall progress for the SDN movement as a whole.”
As Levy and Pitt both point out, early users of SDN technology are very much centred on big service providers, telcos, cloud computing suppliers and so on – businesses that require an agile network infrastructure that can be scaled up and down as required to cope with changes in demand, for example.
Early adopter of open-source SDN
One such company is French cloud provider CloudWatt. The company is headquartered in Paris and was recently fully acquired by major stakeholder Orange.
The company was looking for an open-source SDN platform that would integrate with its existing OpenStack cloud computing platform and enable it to better optimise and customise its network infrastructure.
It also needed to improve transparency to meet European data protection regulations, which state that all privacy sensitive data must be kept within the European Union.
CloudWatt settled on OpenContrail, an open-source cloud networking virtualisation and automation platform. OpenContrail was started by Juniper Networks to foster innovation in the SDN and network functions virtualisation (NFV) fields, according to the company.
“The integration between OpenStack and OpenContrail has given us greatly simplified cloud network design and operations, seamlessly connecting virtual and physical environments,” says Didier Renard, president and CEO of Cloudwatt.
“We remain in control of network customisation and optimisation and are fully compliant with European data privacy regulations.”
The OpenContrail SDN controller used by CloudWatt was developed by Juniper following its $176m acquisition of Contrail Systems in 2012. That was one of a number of acquisitions made by traditional network suppliers looking to shape their SDN strategy.
Sector kingpin Cisco has purchased Clariden, Tail-f and Insieme, and used these technologies to build out its application-centric infrastructure (ACI), which is Cisco’s own version of SDN. The two are certainly similar, but Cisco’s products use a different architecture.
Cisco is betting that customers will still want to buy from a single supplier rather than take a more open approach that SDN offers. Cisco’s outgoing CEO, John Chambers, has even gone as far as saying its offering is outpacing that of rivals offering SDN. This is partly due to being able to get products to the market, he says.
“A year ago we were fighting an SDN perception battle, with competitors using PowerPoint instead of products,” he says. “Today, with ACI, we are bringing programmability and automation to networking on a scale well beyond what competitors define as SDN.
“Now we are in the market with products and solutions and don't see either traditional box competitors or the PowerPoint newcomers able to keep up. We’re winning big time on ACI, and pulling away from the startup competitors. I would say it’s game over, we have got them.”
The end of supplier lock-in?
Open Networking Foundation’s Pitt, however, says “proprietary solutions do negatively impact end users in the long run” and that supplier lock-in is a “problem the networking industry has suffered through for far too long”.
In early 2014, Gartner analyst Joe Skorupa said adoption of SDN technologies would “ramp up” in 2015, and, while SDN is still far from mainstream, it seems that adoption is certainly on the increase.
This is partly because of the need for networking infrastructure to catch up with other parts of the datacentre, and partly because as more businesses sign up for it, the use cases and benefits become clearer to see for other potential users.
“Companies need examples, and they need resources for making the transition. Software-defined networking is virtually the biggest change to take place in the networking industry in the past 30 years, and companies have invested a lot of time, effort and money into their networks,” concludes Pitt.
“Making changes to those legacy networks can be intimidating without case studies and proofs of concept showing that it’s possible, or without a clear game plan in place.”
Securing the controller to address SDN security challenges.