What is Network Function Virtualization (NFV)?

Introduction

NFV stands for Network Function Virtualization, and it’s a way of running network services, such as routers, firewalls, and load balancers, on virtual machines (VMs) instead of physical hardware. This means one doesn’t need to buy expensive and specialized hardware for each network function. One can just use standard servers and run multiple functions on them.

Network Function Virtualization aims to reduce the reliance on proprietary hardware appliances and increase the flexibility and scalability of network services. In this blog, we will explain what NFV is, what its purpose is, what its architecture consists of, and what its benefits are. Let’s begin by first understanding what NFV is.

What is Network Function Virtualization (NFV)?

Network Function Virtualization is the process of decoupling of network functions from proprietary hardware appliances and running them as software in virtual machines (VMs). This allows service providers to run their networks on standard servers instead of proprietary ones. The virtual machines use a hypervisor to run networking software and processes such as routing, firewall, and load balancing. These software-based network functions are called virtual network functions (VNFs).

Examples of network functions that can be virtualized include routers, firewalls, load balancers, VPNs, DPIs, and more.

How Network Function Virtualization Works?

In traditional networks, we are all aware of the fact that there are dedicated hardware appliances that are used to perform specific functions such as load balancing, routing, etc. With Network Function Virtualization, these network functions are virtualized. When we say virtualized, it simply means that they are decoupled from dedicated hardware and run as software applications on standard servers.

Now, the question that arises is how network functions are virtualized.

To make network functions virtualized, NFV makes use of virtualization techniques such as hypervisors or software-defined networking controllers in order to create VMs that can run network functions. These VMs are then further orchestrated and managed by a management and orchestration system. This ensures that the network functions are deployed, scaled, and maintained without wasting any time.

Purpose of Network Function Virtualization

The purpose of NFV is to improve the efficiency, agility, and innovation of network services. With Network Function Virtualization, service providers can:

• Reduce capital and operational expenses by using less physical hardware and more software-based solutions.
• Increase scalability and elasticity by provisioning and de-provisioning VNFs on demand, according to the changing network traffic and customer needs.
• Accelerate service delivery and deployment by launching new network services and applications faster and easier.
• Enhance service quality and performance by optimizing the use of network resources and improving fault tolerance and reliability.
• Foster innovation and differentiation by enabling new business models and revenue streams based on customized and value-added services.

Now that we have a basic understanding of NFV. Let’s see its history.

History of Network Function Virtualization

The history of NFV can be traced back to the early 2010s when the telecommunications industry first realized the importance of virtualizing network functions. In 2012, a consortium of major telecom operators, which include AT&T, BT, and Deutsche Telekom, founded the NFV ISG (Industry Specification Group). They joined together in order to develop a framework for Network Function Virtualization. The first whitepaper published by ISG in 2012 showcased the concept as well as the benefits of NFV.

In the year 2013, the ETSI (European Telecommunications Standards Institute) launched its own NFV ISG. The first set of specifications was released in 2014. Since then, NFV has gained immense popularity among telecom operators implementing NFV solutions.

In 2015, it became a crucial component of 5G network architecture. By the end of 2019, it became a mainstream technology specifically in the telecom industry.

Let’s discuss its architecture along with its components.

Network Function Virtualization Architecture

The NFV architecture consists of three main components: the network functions virtualization infrastructure (NFVI), the virtual network functions (VNFs), and the NFV management and network orchestration (NFV-MANO). Below, we have explained each component in detail with an image.

NFVI (Network Functions Virtualization Infrastructure)

The NFVI is the physical layer that provides the compute, storage, and network resources for running VNFs. The NFVI can span across multiple locations, such as data centers, points of presence, or central offices. The NFVI also includes a hypervisor or a container platform that hosts the VNFs.

VNF (Virtual Network Functions)

The next component of Network Function Virtualization architecture is the VNF. The VNFs are the software implementations of network functions that run on top of the NFVI. The VNFs can perform various tasks such as routing, firewalling, load balancing, encryption, etc. The VNFs can be chained together to form complex network services. The VNFs can also communicate with each other and with external networks through interfaces.

MANO (Management and Network Orchestration)

The NFV-MANO is the functional block that manages and orchestrates the NFVI and the VNFs. The NFV-MANO consists of three sub-components:

• NFV orchestrator (NFVO)
• VNF Manager (VNFM)
• Virtual Infrastructure Manager (VIM)

Let’s understand each of these 3 components.

NFVO

The NFVO is responsible for coordinating the deployment and lifecycle management of network services across multiple NFVI domains. The NFVO also handles resource allocation, policy enforcement, fault management, and service catalog management.

VNFM

The VNFM is responsible for managing the lifecycle of individual VNFs. The VNFM handles tasks such as instantiation, configuration, scaling, updating, healing, and termination of VNFs. The VNFM also interacts with the VIM to request resources for VNFs.

VIM

The VIM is responsible for managing the resources and connectivity of the NFVI. The VIM handles tasks such as provisioning, monitoring, inventory management, and fault management of compute, storage, and network resources. The VIM also interacts with the VNFM to allocate resources for VNFs.

Let’s discuss some of the benefits associated with NFV.

Benefits of Network Function Virtualization

There are many benefits of using Network Function Virtualization for network operations. Some of them are:

• Lower capital expenses: By using standard servers instead of specialized hardware, service providers can save money on equipment costs.
• Lower operational expenses: By using virtualization and automation, service providers can reduce labor costs and power consumption.
• Faster service delivery: By using software-based network functions, service providers can deploy new services and applications in minutes or hours instead of weeks or months.
• Higher scalability: By using dynamic resource allocation and orchestration, service providers can scale up or down the network functions as needed without affecting performance or availability.
• Higher flexibility: By using modular and interoperable network functions, service providers can mix and match different vendors and technologies to suit their needs.
• Higher innovation: By using open standards and APIs, service providers can leverage a wider ecosystem of developers and partners to create new solutions and services.

Risks with Network Function Virtualization

Some of the risks associated with the deployment of NFV are:

• Topology Risks: NFV can lead to complex network topologies which make it challenging to manage as well as troubleshoot issues. This also results in increased downtime and maintenance costs.
• VNF Onboarding Risks: VNF may not integrate seamlessly. Sometimes, this will lead to compatibility issues and a rise in security vulnerabilities.
• Network Activity Less Visible: We all know that network activity can be less visible in a virtualized environment. This further makes it more difficult to detect as well as respond to security threats on time.
• Denial of Service Protection Failure: DoS attacks on virtual networks or VNF public interfaces can drain network resources and disrupt service availability. Similarly, a botnet may infect an unsecured VM, causing a large amount of traffic to other VNFs.

Many network enthusiasts get confused about the functioning and basic difference between SDN and NFV. Let’s discuss it!

Difference Between SDN and NFV

Below, we have explained the basic difference between the two in a tabular form.

Frequently Asked Questions

Q1. What is meant by NFV?

NFV or Network Function Virtualization is defined as the architecture that “virtualizes” network functions into building blocks that can create as well as deliver communication services.

Q2. What is difference between SDN and NFV?

SDN and NFV are both network technologies that aim to increase efficiency and flexibility. SDN separates the control and data planes, while Network Function Virtualization virtualizes network functions on software.

Q3. What is VNF vs NFV?

VNF stands for virtual network function, which is a software implementation of a network function that can run on any hardware platform. NFV stands for network function virtualization, which is an architecture that guides the management and orchestration of VNFs across different locations.

Q4. What is NFV in 5G?

NFV, or network function virtualization, is a framework that uses software and virtual machines to implement network features and services for 5G networks.

Conclusion

In this blog post, we have explained what Network Function Virtualization (NFV) is and how it works. We have also discussed its different purposes, benefits, and architecture, along with its components. We have explained the basic difference between the SDN and NFV. Apart from all this, Network Function Virtualization is crucial and paving the way for emerging technologies such as cloud computing, edge computing, 5G, IoT, and more.

If you have any questions or comments, feel free to leave them in the comment below. Thanks for reading!