What is a Virtual Network Function?

The virtual network feature replaces network hardware with software that can be scaled and scaled to meet growing 5G requirements

VNFs are network services that work as software processes on ready-made server hardware. They replace special hardware devices. By virtualizing key network features that were previously the domain of specialized hardware devices, operators can deploy new services, improve security, and customize network performance on a large scale using software alone.

The individual VNFs are deployed in the cloud as microservices that can work alone or together to provide basic network functionality. Examples include:

  • Network routing, such as domain name service (DNS), natural address translation (NAT) services, and broadband network gateway (BNG) services.
  • Security, such as malware detection, intrusion detection, and virtual private network (VPN) services.
  • Traffic analysis, forecasting and measuring service quality (QoS).
  • Network and resource load balancing.

VNFs: part of NFVI

VNF is often spoken simultaneously with Network Functional Virtualization Infrastructure (NFVI). VNFs are the actual performance of network functions as software processes. NFVI is an architecture or framework for implementing VNF on a large scale. NFVI is a basic concept for the operation of the data center, which is essential for the creation, implementation and effective scale of new 5G services.

NFVI allows Cutting a 5G network, which allows different virtual networks to run on a single physical infrastructure. This allows operators to divide a physical network into virtual networks capable of supporting multiple radio access networks (RANs). It can optimize the allocation of VNF resources for cost and energy, scale VNF, and ensure that VNFs work consistently properly.

“NFV is an architecture that directs management and orchestration activities, while VNF is a technology that provides virtual (that is, hardware-independent) network functions such as routing or a firewall,” said VMware.

“Virtual network functions (VNF) are software applications that provide network functions such as directory services, routers, load balancing firewalls, and more. They are implemented as virtual machines (VMs) and have often been the next step for telecommunications providers in their digital transformation from physical network (PNF) functions to legacy network devices on their own hardware. explains Red Hat.

“Data centers have long used NFV, but the concept has recently been combined with SD-WAN to take advantage of individual and remote branches,” said VMware.


Virtual network functions exist as part of a software-defined network (SDN) continuum, a network architecture concept that completely separates the control plane from the data plane in the network. SD-WAN is a Wide Area Network (WAN), implemented using the principles of SDN.

SDN provides central network control using application program interfaces (APIs). The platform consists of three consecutive layers: infrastructure layer, control layer and application layer, all of which are open. The SDN controller manages operations by transmitting information to systems and routers using the API. Abstracting control from the forwarding plane allows network operators to dynamically regulate traffic flow and thus bring much more flexibility to the network.

SD-WAN allows organizations to intelligently route traffic across multiple WAN connections, which are essential for peripheral computing and low-latency 5G applications. It can provide organizations with better security, higher reliability and optimize the capacity of their networks.

VNFs and 5G

Rapid technological advances, explosive demand from businesses and consumers, and new uses in 5G require operators to make fundamental changes to their network architecture. Dedicated, proprietary hardware limits the growth and flexibility of the operator and does not provide the necessary scale to meet future market requirements.

“Network Functional Virtualization (NFV) aims to address these issues by developing standard IT virtualization technology to consolidate many types of network equipment on industry-standard servers, switches, and high-volume storage. This includes the implementation of network functions in software that can run on a set of standard server hardware and that can be moved or instantiated to various locations on the network as needed without the need to install new equipment. said ETSI.