In recent years, the adoption of software-defined networking (SDN) and network functions virtualisation (NFV) has emerged as a key trend in the global telecom industry. Although the level of adoption is not very high at present, the industry is optimistic about these technologies taking the telecom world by storm over the next few years. As per industry estimates, the SDN, NFV and network virtualisation market will attain a substantial market size by end-2015. Further, the segment is likely to expand at a compound annual growth rate (CAGR) of 37 per cent over the next five years, overcoming the challenges posed by legacy networks.

The existing business models favouring voice services need a serious revamp as Indian operators shift their focus to data. Operators need to transform their network architectures urgently and evolve their legacy networks to make them data enabled. This would need the deployment of technology architectures that offer agility as well as better end-customer experience and operational control. SDN and NFV technologies will help Indian operators transition their networks from hardware- to software-defined platforms, resulting in increased automation. This will result in enhanced operational flexibility and scalability, reduced costs, and dynamic bandwidth and service provisioning.

Defining SDN/NFV

SDN simplifies networking by separating the control plane of a network, which makes decisions related to traffic movement, from the data plane, the underlying system that forwards traffic to the selected destination. In recent times, SDN has been gaining significant traction among enterprises. According to industry reports, the global SDN market for the enterprise and cloud service provider segments will grow from $960 million in 2014 to over $8 billion by 2018, representing a significant CAGR of 89.4 per cent. The forecast takes into consideration in-use physical network infrastructure, controller and network virtualisation software, SDN network, and security services and related applications, as well as SDN-related professional services.

NFV, on the other hand, is about porting the functions of specific network elements virtually. Although it is complementary to SDN and is frequently associated with it, NFV is a unique technology. NFV can abstract any network function typically residing in purpose-built hardware, from that hardware. Once abstracted, the function can be managed as a software module and can also be moved to or replicated on another hardware or computing platform. Thus, NFV makes networks agile, scalable and secure, thereby enab-ling businesses to deploy new services quickly. Network elements that can be delivered virtually include firewalls, session border controllers, radio access network nodes and wide area network acceleration devices.

Moreover, NFV lends flexibility to data centre operators to relocate network functions from dedicated appliances to generic servers and switches. It provides them with scalability to increase or decrease network capacity according to demand. Further, it provides a cost-effective alternative to the expensive hardware deployed for special-purpose applications. These can instead function on less expensive industry standard hardware, with the intelligence being delivered through virtual hypervisors. Opex can also be reduced by managing the virtual system through software, saving money on electricity and hardware maintenance costs.

In addition, NFV significantly reduces the time to market for new services, and delivers a robust and easy-to-operate virtual network for cloud service providers, enabling faster deployment of critical security applications and upgrades.

Operator requirement and readiness

The introduction of next-generation technologies such as 3G and 4G is putting pressure on operators’ existing network infrastructure. Driven by the mass uptake of these services and the growing adoption of over-the-top applications, the bandwidth requirements of operator networks are growing at an exponential rate. Ironically, while operators are optimistic about data driving growth for them, the contribution of these services to their revenue is not very significant at present.

Therefore, a shift to cost-effective and scalable SDN and NFV architectures in the coming years is both logical as well as crucial for sustainability. SDN and network virtualisation will help operators cater to the increasing demand for data capacity while reducing their capex and opex requirements, by reducing their reliance on expensive proprietary hardware platforms. Further, using SDN and NFV, operators can cost effectively implement a host of network functions ranging from standard mobile IP multimedia system  services to features such as deep packet inspection through software. Operators are also keen on virtualising functions and services to provide an on-demand experience to their customers.

However, there exist several issues that pose a major barrier to the adoption of these new architectures. The key among these are huge legacy networks and centralised management of systems. On the technology front, the lack of mature technology, consensus on multiple open-source standardisation initiatives and proven business cases also poses significant challenges.

Operators must have a clear sense of why they are deploying SDN and NFV in the first place. One reason could be to gain a competitive advantage by building the right network cloud architecture, embracing new business models and offering new service capabilities while reducing costs.

Moreover, there is a strong need for operators to restructure their existing organisational set-up by merging network and IT operations, which have so far functioned in silos. Network cloud has brought IT infrastructure under the engineering department and all network functions are likely to be hosted as virtual network functions in the future.

In addition, agility in systems and processes is very crucial for operators, an area in which much needs to be done by operators. Traditionally, they have deployed very stringent and complex frameworks that result in a longer lead time for service order resolution and the development of new services.

Going forward

As the telecom industry adopts the internet-of-things concept, operator networks would need to undergo a transformation to become more agile and scalable. The key elements of future networks will be automation, service programmability and customer self-configuration, all of which will be achievable through NFV and SDN. These technologies will help service providers reduce costs, improve efficiency and effectively utilise resources, as they transform their businesses and networks from being voice centric to data centric.