Software Defined Networking or SDN is a technological approach to designing and managing networks that has the potential to increase operator agility, lower costs, and disrupt the vendor landscape.With SDN the network becomes a programmable fabric that can be manipulated in real time to meet the needs of the applications and systems that sit on top of it. SDN promises fully automated, application-aware and adaptive adjustments to bandwidth, compute power and storage with end-user visibility is what is needed to provide ultimate QoE to the mobile user connected an IP based Telecom network such as LTE .
The root cause of a network’s limitation is that it is built using switches, routers and other devices that have become overly complex because they implement an ever-increasing number of distributed protocols and use closed and proprietary interfaces. By decoupling the network control and data planes, OpenFlow-based SDN architecture abstracts the underlying infrastructure from the applications that use it, allowing the network to become as programmable and manageable at scale as the computer infrastructure that it increasingly resembles. An SDN approach fosters network virtualization, enabling IT staff to manage their servers, applications, storage, and networks with a common approach and tool set.
In a SDN, the network administrator can shape traffic from a centralized control console without having to touch individual switches. The administrator can change any network switch’s rules when necessary — prioritizing, de-prioritizing or even blocking specific types of packets with a very granular level of control. This is especially helpful in a Cloud computing multi-tenant architecture because it allows the administrator to manage traffic loads in a flexible and more efficient manner. SDN allows network engineers to support a switching fabric across multi-vendor hardware and application- specific integrated circuits.
Most of the churn in mobile subscribers today is attributed to poor QoE (Quality of Experience). What’s needed is an efficient and elastic system that adapts to the end-user traffic automatically and dynamically. The rapid adoption of 4G Mobile (LTE) necessitates uninterrupted availability of quality services 24/7 regardless of location or device. SDN has the capability to make this a reality. The Open Flow protocol allows the network to be programmed on a per-flow basis and thereby provides visibility at the user and application level. The capability to increase or decrease the bandwidth needed, for instance, by way of automated bandwidth signalling is one advantage. It can also adjust the number of VMs (Video Messages) and the associated storage needed proactively and dynamically with¬out any human intervention on an application basis.
Developing an SDN business involves the deployment of physical infrastructure, a network controller and a telecoms operating management system which combines operation and business support systems. The network controller is central to SDN with two main functions: virtual resource control and traffic management systems (TMS). The network controller can create a programmable, logical network that allocates resources within the physical network (access and core networks) in the most dynamic way without needing to know the actual infrastructure topology. In so doing, the operator can build the most appropriate virtual network offering multiple services.
SDN is not only an esoteric technology concept but a current reality: in 2012 Google announced that it had migrated its live data centres to a Software Defined Network using switches it designed and developed using off-the-shelf silicon and OpenFlow for the control path to a Google-designed Controller. Google claims many benefits including better utilisation of its compute power after implementing this system. Recently Japanese vendor NEC established a partnership with Portugal Telecom that will see the two firms collaborate on SDN (software defined networking) and virtualisation technology for data centers and carrier networks. The two firms claimed the agreement would enable both companies to test and assess the commercial feasibility and benefits of SDN implementation for carrier data centers , adding that SDN and network virtualisation have “exceptional potential”.
According to Infonetics, telecoms plan to deploy SDNs and NFV by 2014 within data centers, between data centers, operations and management, content delivery networks (CDNs), and cloud services. In most cases, Telcos are starting small with their SDN and NFV deployments, focusing on parts of their network, in “ contained domains “ such as data centers, to ensure they can get the technology to work as intended.
Running in parallel Telco network architects believe that NFV (this term Network Function Virtualisation was coined by the European Telecommunications Standards Institute ) will consolidate many network equipment types onto industry standard high volume servers, switches and storage, thus providing a new network production environment so as to lower cost, raises efficiency and increases agility. Network Functions Virtualisation can be implemented without the prescence of a SDN , although the two concepts and solutions can be combined to unlock greater value.
In the next decade SDN is big business.According to SDN Central (an independent market research community for SDN & NFV), the SDN market is expected to surpass $35 billion in the next 5 years. Adoption of SDN technology has accelerated in recent years from sales of $10 million in 2007 to $252 million in 2012.The emergence of the software-defined networking market is supported by growth in venture capital investment in SDN focused companies. Venture capital funding rose from $10 million in 2007 to $454 million in 2012.
Sadiq Malik ( Telco Strategist )