In today's world, connectivity is everywhere. With the rapid expansion in internet and computer access, and the explosion of mobile, network infrastructures are under more pressure than ever.
As a result, service providers are being forced to constantly enhance their networks to keep pace with persistent growth in capacity demands. To do so, many regularly go out to market seeking new advancements in networking technology and associated next generation management tools, and then assess whether they can be applied to the benefit of their networks.
At a basic level, service providers can opt to meet elevated capacity demands through the addition of cabling and active equipment. However, consumers are increasingly mobile, as demands for 'always-on' connectivity and greater speeds continue to grow. The number of connected services in the home is also growing; by putting mobile at the heart of the connected home, individuals can now be linked to the likes of utility providers, energy giants, insurance companies and goods manufacturers through their network, which provides access to better services, such as optimised lighting and heating. While this dramatically overhauls the consumer experience in the home, it places huge pressure on the reliability of the infrastructure behind the services.
Service providers coping with insatiable capacity demands
Service providers face a dilemma: either add capacity to all impacted nodes to meet anticipated network demand, or "move" bandwidth around the network. The former pushes service providers to create 'over capacity', where capacity at each node is more than necessary, resulting in surplus capacity across the network. The latter on the other hand is a complex process, which demands comprehensive understanding of a network's recent network capacity trends.
Additional issues can also arise in network-intensive businesses and more mature domestic consumers, both of whom are moving their data and IT services into the cloud. This requires service providers to manage data more efficiently to ensure their networking priorities meet agreed business service levels agreements (SLAs), and they provide high customer satisfaction to their demanding user community.
One mooted solution, the 'self-optimisation' of networks, enables the management of network capacity but tends to be reactive rather than proactive. It can create an environment within a complex network where capacity is in a constant state of constant flux, as it attempts to manage real-time demands by interacting with other active network equipment.
By recognising the shifting demands placed on network capacity by timeframe and location, service providers can dramatically improve their ability to efficiently manage capacity, expanding it to match actual demands, rather than more generic capacity needs. But this requires a detailed routing framework, which is where a potentially revolutionary methodology - that of Software Defined Networking (SDN). In it, the network can be dynamically and automatically configured to respond to changing conditions and demands across the network.
SDN: here, and here to stay
There have already been numerous successful deployments of SDN, such as in data centres and for certain aspects of service providers' business routing. It revolves around the concept of a routing table where specific services can be routed based on pre-defined parameters. For instance, an organisation's cloud-based Customer Relationship Management (CRM) service could be routed over a faster network route during normal office hours (a period of higher demand), and then revert to a standard network after this time.
This benefits the organisation because they know their mission-critical systems can operate at high speeds at peak times, and benefits the service provider as they're able to offer a premium service at a higher cost. In this situation, the service provider presents one service with two or more possible routing table entries, and the option to switch the entries between one another based on the relevant time parameter (i.e. between peak and off-peak).
In the initial stages, both situations are easy to manage, as there is a limited and readily controlled set of network parameters. The whole concept starts to become more complex however when we switch routes for a number of services within a larger and more complex network topology.
The role of analytics
Many service providers now use network analytics to model and accurately contrast the capacity of their network with the amount used at node level within specific timeframes. The resultant analytics models are used as the framework for any SDN implementation, because they provide service providers and app developers with the insight and ability to develop alternative routing models which match ever-changing network demands. In future, there is undoubtedly a role for the integration of real-time analytics and SDN, because it allows the majority of network optimisation to be performed in real-time. Of course, this would require a pre-determined set of boundaries for such optimisation to prevent over-compensation - for example, in the event of an outage or a network burst.
Increased capacity and enhanced control
The introduction of SDN into service providers' networks provides them with un-heard of levels of flexible capacity, provided they model network capacity and develop appropriate SDN scenarios to ensure the ongoing integrity of capacity.
Not only does it allow service providers to refine their networks, but it also facilitates the implementation of network scenarios in anticipation of both scheduled events (such as major sporting or entertainment events) and unscheduled events, and put in place specific network configurations to respond to any such situations.
Reducing network complexity
A further benefit of SDN is its ability to reduce network complexity by simplifying network management. This comes from abstracting the complex array of intelligence that resides in the network and consolidating it in the form of an SDN controller - one centralised application that acts as the strategic control point for managing control of the switches and routers in a network. From there, it is then possible to directly control multiple nodes from one source, which in turn makes it easier to route traffic around the network, thanks to a reduction in the number of elements in a network. This means more embedded intelligence can be taken out of the network, analysed, and applied to facilitate more efficient use of capacity on a broader scale.
Underpinning the Internet of Things
In any Internet of Things (IoT) ecosystem where several different devices and services are incorporated into a specific network, it's critical that service providers can manage connectivity dynamically. SDN helps facilitate this by making the introduction of different components (and their services) into the network simple through a series of controllers. This enables providers to quickly virtualise and set up a service at any point in the network as an IoT service, rather than setting it up in the traditional isolated manner, meaning that is quickly integrated with overall network operations.
Moreover, as IoT services evolve, demands for connectivity will continue to grow, largely thanks to an increase in the number of connections to devices and machines that support low data volumes. SDN acts as an enabler behind the scenes, allowing communications service providers and enterprises to simplify connectivity and dynamically allocate resources to manage this trend. Ultimately this helps increase the effectiveness of M2M/IoT services within the core network.
Overall, SDN is dramatically changing the way we manage our networks, especially as they become more complex, and SDN deployments will continue to evolve in accordance with the development of their underlying networks. Moving forward it will be used in ways we can't even imagine yet, as the tools mature and organisations, especially those in the cloud, adapt applications to take advantage of SDN and the opportunities it brings.