Decarbonization with Network Functions Virtualization

by John DeRisi, Lead Product Management & Development, AT&T Business

Network Functions Virtualization (NVF) is replacing traditional hardware-based infrastructures. Operating a network through proprietary hardware is costly, cumbersome, and lacks agility. These traditional systems combine communications services with other hardware, making changes to the network time-consuming. A legacy system also cannot support the data-rich tools and applications that are required for the future-forward business. And because it’s hardware-based, it also requires more energy to operate, which adds to their cost of ownership.

As a solution for these challenges, businesses across industries continue to evolve into more digital, cloud-based operations. Business fiber internet, which provides cloud connectivity, is the bedrock for cloud adoption. This enables for data-rich technologies like Internet of Things (IoT) and artificial intelligence (AI) solutions to operate efficiently. And when the data can be processed and accessed through edge solutions, that is, solutions that operate at the edge of the network instead of through a data center, companies can operate with more efficiency and agility.

Traditional networks do not have the capacity to support this model, but Network Functions Virtualization (NFV) does. By replacing hardware dedicated to running single applications with a single piece of hardware that supports multiple software functions, NFV supports your digital transformation and hybrid cloud adoption.

Legacy solutions like multi-protocol label switching (MPLS) require a backhaul to a data center where services like data inspection, routing, and security typically take place. This can lead to performance issues and delays if your MPLS circuit isn’t fast enough to handle your data.

Today, many businesses are migrating from MPLS to software-defined wide area networking (SD-WAN) to address these concerns. SD-WAN solutions replace MPLS with virtual connections to network functions, so you can shift traffic away from on-premises hardware to the on-premise edge of the network and avoid that backhaul to the data center. Instead, SD-WAN enables you to interact directly with the public and private clouds that host your applications. It makes your network more efficient and improves data access, speed, and security.

It has an environmental sustainability benefit as well. Moving from hardware to a virtualization model enables you to use fewer servers.1 As a result, it can help you reduce carbon emissions substantially by lowering the amount of energy needed for operations and equipment cooling.

Network functions virtualization (NFV) supports software-defined networking

For many companies, SD-WAN is the first step toward a virtual network. Shifting traffic management to the edge computing solutions and into cloud services enables IT teams to have more flexibility. They can tailor policies to meet the needs of various edge zones with different traffic types, locations, and users. These can all be managed through a cloud-based central management console. With this level of control, your IT team can choose the best network transport types for your workloads in the cloud.  SD-WAN provides flexible deployment options and improves efficiency without compromising security.

Network functions virtualization (NFV) makes your SD-WAN even more flexible and efficient. NFV separates hardware from software. The software portions become virtual network functions (VNFs) that do the jobs like routing and optimization that was previously done using multiple pieces of hardware. NFV consolidates hardware into a single device that runs multiple virtual network functions. When the virtual network functions run directly from the cloud, there’s no need for hardware.

SD-WAN solutions are typically deployed at branch sites and cloud data centers. Virtualization enables SD-WAN to work better by ensuring on-premises data centers, colocation data centers, cloud points of presence (POPs), and edge instances all support the same infrastructure as the branch site. This helps prevent delays and bottlenecks and makes transport smooth and efficient.

Virtualization has other benefits, too. It frees your business from hardware-based constraints and enables you to also consider software as a service (SaaS)-based vendors. And as your business grows, the flexibility of NFV makes testing new markets and global expansion easier. A qualified provider can deliver fast deployments so you can implement your NFV solution quickly.

Understanding network functions virtualization (NFV)

The expansion of 5G across the globe and the benefits it brings in fast speeds, lower latency, and broader bandwidth enables businesses to shift operations to edge cloud services. Network functions virtualization supports a modern infrastructure with VNFs that can run on virtual machines in the cloud. Through cloud connectivity, a VNF carries out the same networking functions traditionally performed by hardware but uses software instead. Like SD-WAN, that includes routing, but also firewall functions, caching, load balancing, traffic optimization, network address translation, and much more.

By separating network functions and services from hardware devices, network functions virtualization enables engineers to build on network capabilities by programming all of its different components rather than configuring and connecting devices. As code replaces your traditional infrastructure your network becomes a flexible service platform.

Combine SD-WAN with security-focused virtual network functions and network functions virtualization can improve end-to-end security visibility into your network operations. And if you add visibility-focused VNFs, your IT team can gain deeper insights into network performance to make smarter decisions in operations. This supports network agility for your IT team to respond to business needs more efficiently, which can help to cut costs.

Key components of Network functions virtualization (NFV) architecture

Now that we know what NFV is, let’s look at its architecture and how it can have a positive impact on environmental sustainability. NFV architecture was developed by the European Telecommunications Standards Institute (ETSI), which is an independent, nonprofit, standardization organization for information and communications technology (ICT). The ETSI NFV architecture has three layers: NFV Infrastructure (NFVI), Virtual Network Functions (VNFs), and NFV management and orchestration, or MANO.

NFV infrastructure

The NFV infrastructure is made up of both hardware and virtual resources. Virtual resources are abstractions of the physical compute, storage, and network resources. They are also known as virtual machines. The universal Customer Premises Equipment (uCPE), which is a general purpose, software-defined form of a central processing unit, is at the heart of the physical resources layer and is a key component of virtualization. It combines many single-purpose devices into one multi-function device.

A uCPE device is a white box, meaning it contains only hardware and the bare minimum of software needed for booting itself. It’s a plug-and-play device that typically includes a processor, memory, network interfaces, storage, input and output (I/O), power supply, and wireless capabilities. UCPE devices can be installed anywhere—a telco closet or data center, for example. And there are a range of device choices to meet your needs for speed, memory, and storage..  

With fewer devices, you can help reduce your organization’s power and cooling expenses and its carbon footprint. This infrastructure serves as a flexible foundation for adding multiple virtual network functions (VNFs).

Virtual network functions (VNFs)

Virtual network functions are pre-built to perform services like routing, firewall, network visibility and SD-WAN. VNFs can be combined and stacked just like they are in a hardware-based network. For example, separate VNFs could be launched for each network function—one VNF for SD-WAN optimization, one for firewall, and one for routing—instead of deploying multiple hardware devices.

VNFs free your business from restrictive relationships with hardware vendors and cut the related capital expense. Instead, your network service provider vets and certifies VNFs from a catalog of best-of-breed solutions supplied by different vendors.

Management and orchestration (MANO)

MANO is the framework for managing and chaining all the VNF services in the environment. It deploys and connects functions and services when they’re needed throughout the network. The NFV MANO also must integrate with application program interfaces (APIs) outside the NFV infrastructure. This enables it to work with third-party technologies across multiple networks and operations and billing systems (OSS/BSS).

The NFV architecture and the benefit of adding accessibility to SaaS-based vendors enables you to choose vendors that may help you to reduce your Scope 3 emissions. These are indirect carbon emissions that are not owned by your business, but may be through your vendors. This flexibility allows you to choose those who can do more with less hardware in each area of your network and operations.

Network functions virtualization (NFV) addresses a traditional networking issue: operational efficiency

A traditional wide area network (WAN) uses multiple pieces of equipment, usually from different vendors. These devices include routers, switches, SD-WAN, visibility, firewalls, and more. They can be costly and complex to deploy and manage. Multiply all the devices for each network function by the number of locations, and it can quickly add up to hundreds or thousands of boxes to manage in the network. And having an array of equipment requires an array of in-house expertise.

A virtual network simplifies this by reducing the hardware that’s needed. VNFs built on software make it easier for network administrators to carry out on-going network maintenance. As a result, it’s easier to maintain and reduces costs. In the traditional network approach, a technician is dispatched to carry out changes to network functions. With VNFs, the network support team can remotely access the VNFs to schedule or deploy periodic changes and updates.

You can move, add, change, and delete (MACD) without the need to rip and replace hardware across multiple locations. Broad changes require less time, effort, and reduces the likelihood that commuting is needed for repairs (which can help reduce vehicle carbon emissions). It enables network administrators to manage and orchestrate the wide area network remotely in a central place. And when you no longer need to install racks of equipment, you can get new sites up and running faster and scale quickly.

More equipment also brings more supply chain risk if parts, devices, or machines are not easily available or there’s another form of supply chain disruption. Adopting a virtual network strategy makes you less vulnerable to supply chain challenges and its downstream effects. 

Network functions virtualization (NFV) enhances security

A virtual network provides better visibility and access into the network compared to a traditional hardware-based network. Security measures can be deployed in a near-real-time, modular way. Because VNFs are platform agnostic, administrators can combine security solutions from multiple vendors.

If an incident or breach does occur, such as a distributed denial of service (DDoS) attack on a virtual machine or a VNF, engineers can quickly detect, isolate, and quarantine the affected function. They can then replace it or apply a security patch—quickly, remotely, and on demand.

Another security benefit: Administrators can quickly replicate identical virtual machines in different locations. Software policies that initiate patching and updates can be scheduled for specific times when they impact production the least. Together, the visibility and control afforded by network functions virtualization can play an important part in supporting your network. And when you already have a reliable, secure network, you gain expanded redundancy in network security.

Network functions virtualization (NFV) supports sustainability

Network equipment is a hidden energy cost for many businesses. Traditional networks often have a wide array of tools, applications, and machines relying on it. The direct costs include manufacturing, shipping, consumption, and inner-machine cooling, but associated costs for materials (think ink for a printer), maintenance, and repairs. Add to that the costs and environmental carbon impact of technicians commuting for on-site visits, and so on. In summary, hardware increases a company’s direct energy usage and greenhouse gas (GHG) emissions.

Innovative, connectivity-driven solutions like virtualization don’t just deliver a modern, efficient network. They position you to take advantage of tools and technologies your business needs in order to compete while also helping you reduce emissions, improve efficiency, and realize significant cost savings.

A recent McKinsey report shows consumers don’t just say they support companies that offer more sustainable products. They are increasingly shifting spending to them.2 Regulations are growing, too. An analysis by ESG Book found environmental, social, and governance (ESG) regulations, including emissions rules, rose 155% over the last ten years globally.3 Also, as of the writing of this article, the U.S. Securities and Exchange Commission is expected to release new rules that require publicly traded companies to disclose information about their risks related to greenhouse gas emissions.4 This is for all operations—direct that are owned by the business and as discussed earlier, indirect emissions. Reducing greenhouse gas emissions is no longer an option for enterprises. It’s an imperative.

How AT&T uses network functions virtualization (NFV) for decarbonization

Like you, we’re also striving to meet these new requirements for our customers, our communities, and our business. The AT&T Gigaton Goal, established in 2021 is a commitment to help our customers collectively reduce a gigaton of GHG emissions by the end of 2035. Network functions virtualization and AT&T Smart Climate Solutions such as 5G connectivity and multi-access edge computing can improve operational efficiency, which can help you to reduce energy consumption.

We’ve worked closely with leading non-government organizations, Carbon Trust and Business for Social Responsibility (BSR®), to create a framework for measuring the carbon abatement of our solutions. What we’re learning, we’re passing on to you through education and the products, solutions, and expertise we offer.

One of the measures we’ve taken quantifies energy saved from implementing network functions virtualization. Based on average electricity savings achieved from moving three applications to one uCPE, each uCPE can reduce electricity by 130 watts. If you were to install 3,500 of these devices to perform the functions previously performed by multiple routers, firewalls, and WAN accelerators, the annual energy savings would be an estimated 4 million kWh, reducing greenhouse gas (GHG) emissions by over 2,200 metric tons of CO2e.

  • To put it in more familiar terms, this is equivalent of:
  • Not burning more than 250,000 gallons of gasoline
  • Taking almost 475 cars off the road
  • Switching almost 85,000 incandescent bulbs to LEDs5

Direct energy savings from reducing the number of network devices is an important measure of the benefits from virtualizing your network functions. But it’s not the only one. Our NVF platform goes beyond devices to help you get energy savings benefits, but also, maximum operational benefits. Altogether the benefits from network functions virtualization add up to less complexity with better network performance and lower costs.

AT&T Business is a leader in network functions virtualization (NFV)

AT&T was the first service provider to offer virtual network services in the commercial market. In 2016 we launched AT&T Virtual Network Services in collaboration with Juniper Networks. Today, AT&T Business customers from insurance and apparel companies to manufacturers and municipalities, are beginning to adopt network functions virtualization (NFV) strategies to modernize their networks and reduce greenhouse gas emissions.

AT&T Business offers a range of uCPEs to replace traditional appliances and meet your bandwidth needs for any site. Choices range from an extra-small device that supports one VNF to extra-large devices that run multiple VNFs. Our NFV solutions are both transport- and carrier-agnostic, which means they support a wide range of options including MPLS, internet, and Ethernet.

We also have an ever-growing library of certified virtual network functions for SD-WAN, routing, visibility, and firewall from leading vendors. You can use VNFs to get enhanced control over networking functions, improve provisioning cycle times dramatically, and deploy new applications and services in a matter of hours or days.

AT&T Business Network Function Virtualization solutions includes flexible management options. Choose a fully-managed option so that we do the solution management for you or manage your virtual network—or parts of it—yourself. We work with you to build a scalable, custom solution. You can mix and match sites, platforms, and devices and devise a management strategy that’s right for each.

Our NFV solutions are carrier- and transport-agnostic and available in more than 200 countries and territories. With flexible management options, you’ll get the level of control you’re comfortable with. Your business can gain the impressive benefits of network function virtualization to improve data access and security at the edge of your network while cutting costs and improving how you meet environmental sustainability requirements. 

Why AT&T Business

See how ultra-fast, reliable fiber and 5G connectivity protected by built-in security give you a new level of confidence in the possibilities of your network. Let our experts work with you to solve your challenges and accelerate outcomes. Your business deserves the AT&T Business difference—a new standard for networking.

Learn more about AT&T Network Functions Virtualization by downloading our product brief.  To connect with an expert who knows business, contact your AT&T Business Representative.

1“Virtualize Servers,” EnergyStar, Accessed November 13, 2023,

2McKinsey & Company and NielsenIQ, “Consumers care about sustainability—and back it up with their wallets,” February 6, 2023

3ESG News, “Global ESG Regulation Increases by 155% Over the Past Decade,” June 20, 2023

4Zack Warren, “Upcoming SEC climate disclosure rules bring urgency to ESG data strategy planning,” Reuters,  January 30, 2023,

5All equivalencies in this document are estimated using the methodology outlined by the U.S. Environmental Protection Agency, Greenhouse Gas Equivalency Calculator. (Note, the average eGRID electricity factors have been used rather than the marginal AVERT electricity factors, this being a more conservative estimate of the savings).