What is Network Function Virtualization ?

Network function virtualization (NFV) is simply the replacement of network hardware with virtual machines (VMs). NFV is a network architecture concept wherein network functions are decoupled from the hardware using virtualization technologies. VMs use a hypervisor to run the networks as software and they carry out processes like routing, load balancing, and processes in content delivery networks. NFV involves cloud and virtualization techniques that provide enhanced network services with elastic scalability and automation.

How does NFV work?

NFV replaces traditional hardware components with VMs; these VMs run software that accomplishes everything the traditional hardware did. These functions include routing, load balancing, network slicing, network monitoring, security functions, and session border control. A hypervisor allows network admins to configure, automate, and manage the virtual network. 

NFV architecture

The European Telecommunications Standards Institute (ETSI) proposed the NFV architecture to define standards for NFV implementation. 

A typical NFV architecture comprises of:

Virtualized network functions (VNFs):

These include software applications that provide network functions like file sharing, IP configuration, load balancing, routing, and directory services.

Network functions virtualization infrastructure (NFVI):

This is the complete hardware and software environment where NFV is deployed. This may consist of a hypervisor or a container management platform that combines the compute, storage, and network resources.

Management, automation, and network orchestration (MANO):

This framework manages the infrastructure and provisions the new VNFs.

Benefits of NFV

Less dependency on hardware

NFV functions can be run on standard hardware, no dedicated hardware required. This means multiple network functions can run on a single server, reducing the dependency on traditional, physical hardware. This helps reduce the amount of space and power used and costs spent on maintenance, the cooling system, and hardware replacements.

Flexibility

You can easily move your NFV resources from one server to another as needed. You can also change the network infrastructure based on your organization's needs since not much physical hardware is involved.

Scalability

You can easily scale your NFVs up or down based on incoming traffic. This simply involves adding or removing VMs and their related resources.

Challenges of NFV 

NFVs possess all the risks that any software is exposed to.

Security

NFVs are vulnerable to threats and hacks, unlike the physical hardware protected in a data center. It is easier for malware to penetrate software components and infect them.

Backup and recovery

NFV environments consist of MANO and a virtual infrastructure manager (VIM). It is critical to back up the services and components that run on them to ensure recovery in the case of data center infrastructure failure issues.

Lack of a common framework

NFV software from one vendor cannot be used with equipment from another vendor. This is a major operational challenge for network admins as there is no direct system or software that provisions VNF interoperability.