What is Network Functions Virtualisation (NFV)?

What is network functions virtualisation (NFV)?

Network functions virtualisation (NFV) is a modern architecture approach that decouples the network's various applications from its hardware resources, including computing, storage and other network hardware. This creates a virtualised layer of network functions deployed as virtual machines (VMs) or containers that all network applications can share.

NFV networks are more agile, scalable, customisable and manageable. A centralised control panel enables network operators to automate the provisioning and orchestration of network resources and quickly respond to changing traffic patterns and network demands.

NFV allows communication service providers (CSPs) to manage, orchestrate and expand network capabilities on demand, wherever required. Most 5G networks run on NFV infrastructure.

NFV vs SDN (software-defined networking)

NFV and SDN are software-defined approaches that create a virtualised layer on top of a physical network to make networks more flexible. While SDN is focused on data centres, NFV is geared toward wide-area networks (WANs) and network service providers and operators.

NFV virtualises network functions and reduces the need for physical devices, while SDNs help organisations centralise network management and improve network traffic routing.

Virtual network functions can be deployed across an SDN ecosystem. Used together, SDN and NFV help create agile, flexible networks capable of managing complex virtual environments.

How does network functions virtualisation work?

NFV typically consists of many architectural building blocks, including:

A hardware layer of compute, network and storage resources
Virtualised resources, such as virtualised network functions (VNFs) or cloud-native container-based microservices
A virtualised execution layer that provides orchestration and runtime environment for VNFs, containers or cloud-native functions
A management, automation and network orchestration (MANO) layer

Virtualised network functions (VNFs)

VNFs are the services previously running on physical hardware. Routing, firewalls, IP configuration and intrusion detection systems, SD-WAN systems and file-sharing programs are standard virtualised network functions.

When virtualised, these services can link together in ‘service chaining’. Service chaining helps network operators automate the provisioning of resources for every service on the network. A centralised view of all functions gives operators enhanced network control and enables them to steer traffic and workloads to available servers, reducing the risk of service outages.

Management, automation and network orchestration (MANO)

MANO is the basic framework for managing virtualised network functions' deployment, provisioning, monitoring and performance. It also creates an interface for NFVI to communicate and interact with existing operating support systems (OSS) and business support systems (BSS).

MANO is divided into three subsections:

NFV orchestration uses virtualisation technologies to deploy new network functions, provision resources to existing VNFs, and authenticate NFVI resource requests.
A virtualised infrastructure manager (VIM) optimises the software lifecycle, virtual resources and physical network. VIM instances can manage multiple NFVI resources or specialise in a specific aspect. A VIM records virtual and physical resources, allowing network operators to maintain operations and deploy new services.
The virtualised network function manager standardises virtual network functions and increases the interoperability of SDN features. VNF management includes instantiating or creating instances, scaling, upgrading and terminating virtualised network functions (VNFs).

Network functions virtualisation use cases and applications

The emergence of NFV has powered a new range of technological possibilities on the network, such as:

Virtualised Evolved Packet Core (vEPC): VEPC virtualises the mobile core network components (such as mobility management, authentication and data routing) traditionally handled by physical equipment. This facilitates 4G/5G mobile networks, supporting dynamic scaling during peak usage, such as significant events or natural disasters.
5G network slicing: Network slicing creates multiple virtualised and isolated network slices tailored for specific use cases (e.g., Internet of Things (IoT), autonomous vehicles or mobile broadband).
Virtualised Customer Premises Equipment (vCPE): vCPE replaces physical hardware at customer sites with cloud-based virtualised functions like firewalls, routing and VPNs. This is typically used for managed services for enterprise customers, allowing simplified remote deployment of new services.
Cloud-based content delivery networks (CDNs): CDNs use NFV to virtualise CDN functions, such as caching and video optimisation. This technology can be used for video streaming platforms and high-demand events like sports tournaments.
IoT connectivity management: NFV helps manage large-scale IoT networks with virtualised gateways, security functions and traffic optimisation. This powers applications like smart cities and Industrial IoT (IIoT) in factories.
Edge computing: NFV deploys virtualised functions at the network's edge to enable low-latency services, such as real-time gaming, AR/VR and remote industrial automation.

Benefits of network functions virtualisation

By making networks more resource-efficient, performant and agile when launching, scaling and managing new services, NFV allows CSPs to meet and stay ahead of the growing demands of today’s high-performance networks.

Here are some of the significant benefits of NFV:

Reduced costs: The shift from purpose-built hardware to general-purpose servers lowers deployment and maintenance costs.
Improved performance and scalability: NFV allows CSPs to upscale and downscale network functions based on demand, improving load balance and meeting traffic spikes.
Faster service delivery: With vendor-agnostic multi-tenant support, multiple virtual and cloud-native network functions can be aggregated onto a single platform, meaning various services and applications can be simultaneously served and scaled.
Innovation on demand: Shifting to NFV significantly improves the speed and agility with which network functions and services can be launched, updated or sunsetted.

NFV is redefining network operations in a digital-first era. From enabling cost-effective scalability to powering cutting-edge solutions like 5G and IoT, NFV empowers organisations to stay competitive in a rapidly changing landscape. As businesses adopt telecommunications solutions to optimise their networks, their role in driving efficiency, innovation and digital transformation will only grow.