Just when you think you know where networking is going and what the industry is doing, BAM! Something comes along that adds a new dimension and puts us right back onto a steep learning curve. Software Defined Networking (SDN) is one such movement that currently has the networking industry abuzz.
One definition of SDN describes it as “an emerging network architecture where network control is decoupled from forwarding and is directly programmable. Network intelligence is centralised in software-based SDN controllers, which maintains a global view of the network.” The concept is akin to that of an API in the software world and would allow the network to be controlled and programmed through the use of software and an open interface that talks to the underlying network hardware.
It is claimed by some commentators that SDN will be a major disruptive force in networking that will accelerate innovation and open the industry up to more competition at the network software and hardware layers. This is due to the use of open standards on the interface between the control plane, data plane and hardware, and allows many companies to create offerings and technology that can be part of the ecosystem, e.g. the processor chips inside network switches can be based on merchant silicon and don’t necessarily need to be purpose built silicon chips which is the case with the majority of network appliances today.
SDN has fuelled a significant amount of industry activity, including:
- Creation of the Open Network Foundation (ONF) in 2011, which is a non-profit consortium of vendors and end user organisations that promote the use of SDN and have defined an open interface to the network called Openflow;
- Many networking start-ups and investment activity, e.g. Ncira, Embrane, Bigswitch, Plexxi and Insieme to name a few;
- Many networking vendors announcing their support of Openflow, including HP, Brocade, Extreme and NEC; and
- Cisco announcing Open Network Environment Platform Kit (OnePK) which will be their programmable interface to their switching and routing products.
It is still early days with vendors jockeying for position and mindshare, a handful of early deployments and no standards ratified by the standards bodies yet, but SDN holds promise. The very high pace of change in IT driven by technical advancements, economic pressure and social changes in the way we communicate and work, is placing organisational networks under significant pressure. The network is the foundation upon which all the above runs and is successful, and it needs to be as flexible as the applications, workloads and users who rely on it every day.
Having a network that is supportive, yet dynamic and flexible through programmability will be a real breakthrough for organisations, but SDN will just be another architectural choice that our clients will need to make. The right choices can sometimes be difficult for organisations to make considering the myriad of options already available, and managing transitions between existing and new age architectures is additionally no mean feat. This will require significant depth of knowledge in networking and management of large projects so consider partnering with an appropriate services organisation as SDN matures and becomes a viable architecture choice.