In today’s networking world, Cloud IT is understood to be mandatory for Enterprises. Cloud is required to successfully participate in the global digital economy. So how do we enable the cloud to drive business agility?
The heart of the cloud is the data center and over the past five years there has been a rigorous IT program to evolve the compute and storage platforms. However while the IT stack has made huge strides in agility through the adoption of virtualization of the compute and storage assets in the data center not the network that underpins this business information has lagged. Limiting the overall efficiencies businesses are getting from their virtualization investments.
This lagging is not caused by the hardware capacities or bandwidth of the network, far from it. The capacity and speed aspects of data center networking have tracked well ahead of compute power with the availability and density of 10Gigabit, 40Gigabit and even 100Gigabit. The issue has been with the limited evolution in the management and configuration of these networks.
The data center network environment has not radically changed since the beginning of the century. Data center networking in the early 2000’s revolved around repurposed LAN hardware and a set of network protocols that were developed for the business office environment.
Progress was made in the late 2000’s with purpose built data center switching and new protocol implementations fashioned together as proprietary data center fabrics. These provided a more robust data center networking environment but at a high cost in both proprietary capital investment and high operational complexity, requiring specialist technical certifications and dedicated resourcing.
Even with this network innovation there remained a level of complexity that negated the increases in capacity. The management and configuration workflows to augment and adapt the network to the changing application environment hadn’t significantly improved. If anything they had regressed with increased operational complexity forcing a greater level of governance to limit network changes impacting the critical business applications. Change was required if the power of compute virtualization has to be truly delivered as there was disconnect between the worlds of IT (application) and IP (network).
This change came with a rethink of the dynamics between the network hardware and the network intelligence and has evolved as Software Defined Networking (SDN).
SDN has received a lot of press in the IT and IP marketplace and after a few years as an emerging technology has developed into the solution to drive the efficiencies in networking to enable Cloud IT.
The key difference SDN delivers over traditional data center networking is the separation of the network intelligence (control plane) from the network hardware (traffic forwarding).
This allows data center architects to centralize the control plane so that configuration points are minimized, reducing the complexity of maintaining the network topology. It’s also changed the procurement of network hardware in the data center, with a wider range of hardware options for the various networking roles.
Many businesses around the world are adopting SDN to refresh their existing data centers and are doing so without the traditional rip and replace hardware upgrades of the past.
Instead SDN is being implemented as an overlay network on top of the existing network equipment. Businesses are deploying SDN based network controllers to separate the application forwarding decisions from the network hardware (switches and routers). They have found that by moving the forwarding intelligence to the compute layer where the application sits has simplified the overall network configuration and improved its agility and responsiveness to application changes.
The future of data center networking has been set; Enterprises, and web-scale companies are reaping the benefits of SDN in the data center today and its use across the globe will only increase as its the go to technology for Cloud IT networking.
So if this future is set, and the underlying technology decision been made the key question now is how do you choose the right SDN? That’s my topic for the next blog. Stay tuned.
About the Author
James McInroe is Marketing Director for the Alcatel-Lucent (News 
- Alert) (News - Alert) Software Defined Network venture Nuage Networks. He is focused on the key product and solution launches for network virtualization of the data center network and beyond including the launch of Virtualized Network Services (VNS), and is a frequent and popular blogger on the subject.
Edited by Peter Bernstein
