Thanks to advances in virtualisation, IT departments can now easily provision additional virtual compute and storage resources as needs change; virtualisation has also been the catalyst for the explosive growth in cloud computing services.
In a recent IDC survey on the adoption of cloud services in Asia Pacific, the analyst group found that regional CIOs are planning to increase their spending on public cloud services and technologies in 2013 by 50 percent to US$7.5 billion. A Forrester analyst predicted that 77 percent of enterprises will be using virtualisation by the end of 2013, and that six out of 10 workloads will be run in virtual machines.
Yet, despite the advances in computing capabilities over the past three decades, the way networking is carried out has remained virtually unchanged. For the last 30 years, networks have been built based on a simple concept: that the intelligence to control data flows is embedded into the switches and routers themselves. The enterprise network, originally conceived as a fixed infrastructure to serve a relatively static business environment, is increasingly forced to contend with the conflicting demands of a very diverse set of services that fluctuate in real time. This puts enormous strain on those who manage the system.
If control rules needed to be changed, network administrators would either have to do them directly on the devices, or get the switch vendor to write a change into the software - a process which could take months. In a sprawling network consisting of hundreds, if not thousands, of network devices that may come from different vendors, the complexity and costs associated with such changes can quickly escalate. Virtualisation and the introduction of cloud-based services in the form of SaaS, PaaS or IaaS compound the problem by introducing rapidly fluctuating demands on the network at machine speeds. To cope, businesses have thrown money at the problem.
It's for these reasons that the concept of software-defined networking (SDN) has generated a lot of excitement and buzz in the market. SDNs are designed to take much of the network intelligence found in switches and routers, and centralise it into software-based controllers. Network administrators can easily programme and manage networks from a centralised software console, without needing to worry about the underlying hardware in the network. As a result, IT departments can build networks that are more flexible, dynamic and easier to program, as well as less complex and less costly.
SDN - bringing networking into the 21st century
Can SDN justify its hype? It's clear that data centre operators are finding it difficult to introduce new revenue generating services and optimise their costly network infrastructures which span from the core to the edge. Networks also continue to grapple with known issues in security, robustness, manageability and mobility. According to PwC's 16th Annual Global CEO Survey, more than four-fifths of CEOs surveyed indicated volatility and uncertain market conditions as the main challenge faced by their respective businesses. If the network can't keep up with rapid changes, it's unlikely that the compute and storage resources built on top of it - no matter how powerful or flexible - can.
Sign up for Computerworld eNewsletters.