Artur Marciniec - Fotolia
The cloud is now common parlance in the world of technology. Those fluffy skyward thoughts have become hard datacentre realities for enterprises across the UK and the world.
But when it comes to going virtual, there is one that has been slower on the uptake: the network.
The past 18 months have seen a raft of major telcos embracing the functions of software-defined networking (SDN), milking the benefits of increased flexibility and a reduced time to market for services.
After some hesitation, enterprise-level businesses are looking at what additional capabilities they could harvest from embracing the tools. But it is not just a case of changing technologies, it is one of changing cultures.
“A standard network manager really only cares about the hardware and the network operating system,” says Clive Longbottom, leading analyst at Quocirca.
“They look at how packets are moved around based on aspects such as quality of service as decided by rules applied to routers and switches.
“They may occasionally lift their heads slightly above the parapet to look at things such as firewalls and other edge of network appliances, but they prefer that things such as the business rules that these deal with are defined – and often implemented – by someone else.”
This age-old way of the network manager has worked for a long time. The network is arguably the most important element of the infrastructure as, without it, nothing else will function. To more elements is a huge task with multiple dependents and, as such, it is not a decision taken lightly.
It has been the network manager’s job to have a strong focus on the hardware, ensure that the system is running and, in turn, that the company is running. Now that already difficult job has become even more complex.
“An SDN network manager has to get far more involved with what is happening across a broad platform,” says Longbottom. “Those precious data packets that were dealt with by application-specific integrated circuits [ASICs] and central processing units [CPUs] at the device-level now go up to servers that can take more nuanced and detailed action on the data.
“Suddenly, the network manager has to understand servers – and start to understand the business of the organisation that is paying their salary.”
Integrating SDN into company culture
Suppliers touting their products to heads of IT are keen to sell on the benefits that virtualised network can bring to a firm, but they are not blind to the realities of reticence from the traditional network manager.
“The benefits of SDN have been widely discussed,” says Scott Sneddon, senior director of SDN and virtualisation at Juniper Networks. “These benefits allow network managers to provide more agile services through automation, abstraction and tight integration with devops and cloud operations tools.
“But to realise the greatest possible benefit, the IT department needs to look at their culture and organisation. Network management teams need to work closely with the cloud and devops teams to eliminate the silos of responsibility that have existed in the past.”
Sneddon says the traditional delegation of all network management and provisioning tasks – tasks that have always been labour intensive – have created delays in new service implementation and severely hampered agility.
But although it means the bigger shake-up, it is just these companies that can benefit from the new tools on offer.
“These businesses are looking at the entire business problem that they are trying to solve, and are bringing together cross-functional teams to address these problems,” says Sneddon.
“The network management, cloud management, security and application development teams all have a seat at the table. There is a culture of knowledge sharing and collaboration.”
The user experience
While SDN is not yet in every enterprise, certain sectors have been willing to get on the train earlier than most. Education is one such example, including at City, University of London.
The organisation has increased its network capacity and resilience, as well as reduced the amount of time it spends deploying network upgrades, after moving its network onto Avaya’s SDN system, Avaya Fabric Connect.
The university’s IT department serves around 17,000 students, 2,000 staff and 600 visiting lecturers across four campuses and a number of additional specialist centres. It manages a network that must – at peak times – accommodate 5,000 Wi-Fi network users and 6,000 wired connections.
So the benefits of moving to SDN and a more agile network are clear. However, this is a university with a long history – dating all the way back to the 1890s – and there was no question legacy hardware and old-school network managers were going to be present.
Claire Priestly, the university’s head of IT, says SDN is an evolution more than a revolution.
“The step was to the fabric network onto our main campus and datacentres,” she says. “The improvement in resilience was exceptional and immediate – bottlenecks and congestion in our network traffic disappeared overnight, and we saw a reduction in our recovery time from up to five minutes prior to implementation, down to 20ms.
“It was huge step forward from a security perspective too. As a university, we have more than 17,000 students and, as such, more than 17,000 potential hackers. We now have the ability to create fully segregated and secure networks in minutes, which revolutionised our scalability and responsiveness.”
But there cannot be a denial that there had to be a change in mentality for the IT department to get the full technical effects of SDN.
“The cultural shift in IT was minimal and largely front-loaded,” says Priestly. “Our network manager Paulo Leal had to get his head around the shift in mindset [where he] had to forget about traditional switching.”
Claire Priestly, City, University of London
But that traditional attitude also meant he could appreciate the rewards.
“The turning point for Paulo was making our datacentre fully resilient and automating its recovery,” says Priestly. “As a risk-averse network manager, he was quick to recognise the benefits that a fully automated recovery could offer to our services and users.
“It’s Paulo that has since been the key advocate of the network upgrade project. He says the upgrade was ‘delivered by email rather than truckload’ and when the Avaya fabric-capable switches were installed for the datacentre, he tolds me it took longer to unload the kit for the fabric network than it did to actually configure the whole fabric cluster.”
Priestly says adopting SDN has meant they no longer have to worry about resilience in the core – the major concern of all traditional network managers.
“One day there was a complete power failure in one of the buildings where a core switch is located,” she says. “It was the ultimate test – and there was absolutely no impact on users.”
It has gone so well for the university that it is now looking to the next steps, including extending the network to their satellite sites.
“The benefits of SDN are huge. We can do more with less, in a simplified but robust manner, taking advantage of all that our infrastructure suppliers offer,” says Priestly.
So, it is clearly working for Priestly and her team, but there are many more network managers who need to look to their futures.
“SDN is being embraced reasonably well so far,” says Longbottom. “OpenFlow is making some headway – not always as a 100% standard, but it is at least providing a degree of fidelity in data flows.
“However, where the network manager rightly fought back was around how a ‘pure’ SDN approach built in too much latency to certain data flows.
“This has led to the emergence of both network function virtualisation [NFV] and of hardware-assisted SDN, where certain functions are still carried out at the switch/router level – as it makes more sense for these functions to be done at line speed in real time.”
It isn’t going to be simple then. It is still an emerging technology and one where network managers must be prepared to expand their skills.
“The real challenge comes in the willingness of a network manager to look beyond traditional supplier-led training and certification, and develop new skills and understanding,” adds Sneddon.
“Today’s strongest network engineers are learning basic programming languages to develop automation tooling, are enhancing their Linux skills and are getting involved in cloud projects such as OpenStack and Kubernetes. They are evolving into true systems engineers.”
But they cannot do it alone and it is something their companies need to understand too.
“This sort of skills development for network engineers also needs the support from leadership to become a priority,” says Sneddon.
“Fortunately, more businesses are investing in a wider range of skills development for their IT employees. As SDN technologies continue to mature, so do associated training programs.”
So while there must be a change in the attitude of the traditional network manager, it is one that needs to be supported by the wider enterprise, and one that network people will be willing to take – as long as those benefits are proven to work.
Read more about SDN
- Early VMware NSX adopter BayState Health is weighing the possibility of a future as an SDN service provider, using multi-tenancy to run other organisations’ networks parallel to its own.
- There’s a lot of talk about digital transformation in the tech industry, but to obtain it, enterprises need to undertake network transformation. That’s where SDN can help.
- To seriously jump-start SDN, automated service lifecycle management is needed for operations efficiency and service agility for legacy and SDN networks.