The growing size and complexity of telecom networks has driven the demand for software-defined networking (SDN) and network function virtualisation (NFV) solutions. These solutions can simplify and maintain the entire network efficiently. They offer flexibility in controlling traffic across the network, thus improving network performance. In fact, the dual characteristics of softwarisation and virtualisation allow developers and operators to build both application-aware and network-aware applications to meet their business demands.

Further, the need for virtualised networks has been amplified due to the onset of the Covid-19 pandemic, with a growing number of companies migrating to web-based applications and services. In fact, organisations that introduced SDN and NFV solutions into their networks during the Covid-19 pandemic were able to quickly adapt to the traffic dynamics and network specifications that emerged from the work-from-home mandates. To meet the rising demand for streaming and video-based applications and social media platforms during the pandemic, telcos resorted to softwarisation and virtualisation to ensure minimum intervention at individual sites. Going forward, as 5G networks become the norm globally, SDN and NFV technologies will be crucial for building programmable, flexible and customisable networks.

Key demand drivers

The outbreak of the Covid-19 pandemic has been a major demand driver for the adoption of SDN and NFV solutions, as it has led to a shift towards cloud services in many organisations. These technologies enable smooth integration with the could and lower operating costs, and allow the comprehensive management of infrastructure. Further, cloud service providers are leveraging SDN capabilities to build an integrated network for augmenting the flexibility and scalability of cloud-based platforms.

When coupled with virtualisation, SDN provides improved agility for deployment and effective resource utilisation. Moreover, SDN/NFV solutions help minimise the capex and operational cost burden faced by companies while reducing the dependency on hardware platforms.

The Covid-19 pandemic has also been a major factor driving the interest of enterprises in software-defined wide area network (SD-WAN) technology. The high cost of enterprise-quality bandwidth and the shift towards remote working have led enterprises to install SD-WAN solutions, which enable bandwidth aggregation and optimisation while providing high-level network security. A number of financial institutions and other enterprises in India have recently floated tenders for deploying SD-WAN. The government, too, has become more aware of the need for deploying cutting-edge technologies to meet the growing demands in the post-Covid era.

Features of SD-WAN 

SD-WAN is a technology that uses centralised control to securely direct traffic across WAN, thereby increasing application performance, enhancing user experience and reducing IT-related costs for enterprises. The technology can help solve problems such as bandwidth costs and traffic latency, allowing enterprises to move beyond multiprotocol label switching (MPLS) and leverage a combination of transport services including MPLS, LTE and broadband internet services to securely connect users to applications. A large number of enterprises have started deploying SD-WAN to enhance their digital networking experience. Telcos can tap this opportunity and explore partnerships with technology vendors to offer SD-WAN services to enterprises.

Going forward, the adoption of SD-WAN solutions is expected to increase rapidly. Industry reports suggest that by 2022, 90 per cent of the existing router refreshes will be replaced with either virtual customer premises equipment or SD-WAN solutions. Moreover, the onset of the 5G revolution in India will drive enterprises towards more intelligent, robust and flexible network solutions such as SD-WAN, which is capable of coping with the agility and velocity of dynamic and hybrid IT environments.

Role of SDN/NFV in 5G deployments

A key feature unique to 5G is network programmability. In the 5G era, a gamut of new communication demands will emerge from a range of devices, users and companies. To sufficiently manage these demands, 5G networks will have to be programmable, flexible, modular, software-driven and managed in a manner that they support a diverse range of services. In fact, all individual domains of the network – mobile core, radio access network and transport network – will require a high level of programmability and flexibility.

SDN technology can play a key role in this regard by enabling network programming. A programmable 5G network provides service agility by reducing the time for service creation and adaptation; service diversity by having a single infrastructure for multiple services with a wide range of requirements; and resource efficiency by dynamically allocating the right number of resources wherever needed.

Another disruptive concept that will emerge in the 5G era is network slicing. Through network slicing, a single 5G physical network can be sliced into multiple isolated logical networks of varying sizes and structures, dedicated to different types of services. It will allow operators to create different levels of services for different enterprise verticals, enabling them to customise their operations. As per a GSMA report, network slicing will be critical for unlocking the enterprise opportunity, amounting to $300 billion by 2025, in the 5G era. To leverage these benefits, operators will have to adopt NFV solutions, which provide the necessary infrastructure for orchestration and automation of network slices. Each of these network slices will have its own characteristics in terms of speed, latency and quality of service.

Apart from 5G, SDN and NFV hold the promise to support emerging applications such as enhanced mobile broadband, ultra-low latency and massive sensing type applications while improving network resilience. Service providers and enterprises across verticals such as connected cars, IoT and e-Health can leverage SDN/NFV to provide flexible and cost-effective services without compromising the end user quality of service.

Challenges hampering deployment

While SDN and NFV technologies promise a variety of benefits, they are not devoid of challenges. As per industry reports, the primary factors that inhibit service providers from adopting SDN and NFV solutions are the lack of orchestration, active business cases and capabilities needed to operationalise SDN/NFV services. Further, complexities associated with the integration of third-party virtual network functions, organisational problems, and the lack of cohesive industry standards are significant obstacles.

Another major challenge associated with SDN and NFV-based networks is related to security. Operators have now started introducing various virtualised network elements, including virtualised evolved packet core, virtualised IP multimedia services, virtualised residential gateway and virtualised next-generation firewalls, in their access and core networks. However, very little attention has been given to the security aspects of virtualisation. While several standardisation bodies have started looking into the security issues associated with the use of SDN/NFV technologies, a lot of work is still needed in this domain. Stakeholders including vendors, operators, universities and regulators need to come together to address these issues.

The deployment of SD-WAN also poses major challenges. A key issue is that SD-WAN solutions designed for one use case, such as connecting branch offices of an enterprise located in a specific area, are not always suitable for other use cases, such as trying to support a global deployment. Another big problem is securing these new, highly dynamic connections. In view of these challenges, an increasing number of enterprises are opting for managed SD-WAN solutions.

The way forward

Net, net, the adoption of SDN and NFV technologies is critical for telcos to move towards a new 5G-based network architecture. Telcos can leverage the emerging opportunities in the enterprise space and partner with various IT vendors to help enterprises across industry verticals build programmable and flexible networks. To this end, they need to work with global co-location and interconnection providers offering carrier-grade infrastructure and a wide range of easy-to-deploy SDN and NFV solutions. This will help them realise the full potential of 5G services, and build flexible, scalable and customisable networks for the future.