Network Functions Virtualisation: Complete guide

Introduction

The Network Functions Virtualisation (NFV) market is set for remarkable growth, projected to increase by USD 90.1 billion with an impressive CAGR of 31.39% from 2023 to 2028. This spike is driven by several key factors, including advancements in network infrastructure, the rise of smart-connected devices, and the widespread adoption of wireless networks.

NFV transforms traditional networking by replacing physical devices, like routers and switches, with Virtualised Network Functions (VNFs) that run on standard servers. This approach allows network functions to be abstracted into flexible building blocks, making it easier to create and deliver communication services. 

In this article, we go into more detail about what Network Function Virtualisation in 5G is and the benefits of network function virtualisation. Read along!

What is Network Functions Virtualisation (NFV)?

Network Functions Virtualisation (NFV) is a network architecture approach that shifts essential network functions, such as load balancing and encryption, from dedicated physical hardware to virtual machines (VMs). This transition enables organisations to streamline operations, reduce costs, and accelerate service deployment.

In a traditional setup, each network function—like firewalls, routers, and gateways—operates on specialised hardware designed for that specific purpose. This hardware can be expensive and difficult to scale as business needs grow.

When upgrades or new installations are required, organisations often face long lead times, significant investment, and compatibility issues with new technologies. This dependence on physical devices can hinder an organisation's ability to adapt quickly to changing demands.

Network Function Virtualisation in 5G addresses these challenges by decoupling network functions from physical appliances. Instead of relying on costly hardware, service providers can utilise standard servers and switches to run multiple network functions as software applications within virtual machines. This flexibility allows operators to easily spin up new VMs whenever a new service is needed, significantly speeding up the deployment process.

Key components of Network Functions Virtualisation

The European Telecommunications Standards Institute (ETSI) identifies seven primary components that form the backbone of NFV architecture. Let’s explore each one of these components in detail.

1. Virtualised Network Functions (VNF)

Virtualised Network Functions (VNFs) are software applications designed to provide specific network services. These functions replace traditional hardware appliances. Examples of VNFs include routing, firewalls, and intrusion detection systems. By running these services as software, VNFs allow for greater flexibility and easier updates compared to hardware devices.

2. VNF Manager

The VNF Manager oversees the lifecycle of VNFs within the NFV environment. This includes the installation, maintenance, scaling, and removal of VNFs. If your NFV ecosystem uses multiple VNFs, having a dedicated manager helps ensure that each function operates smoothly and efficiently.

3. Element Management (EM)

Element Management (EM) focuses on managing the performance, faults, configurations, and security of VNFs. This component ensures that VNFs are functioning correctly and optimally. EM plays a crucial role in monitoring the overall health of the virtual network.

4. NFV Infrastructure (NFVI)

NFV Infrastructure (NFVI) consists of all the physical and virtual resources needed to support VNFs. This includes servers, storage devices, and networking equipment. NFVI offers a virtualisation layer via software known as a hypervisor, which enables several virtual machines to run on a single physical computer. This setup creates a flexible environment for deploying and managing VNFs.

5. NFV Orchestrator

The NFV Orchestrator is responsible for creating, managing, and terminating network services based on VNFs. It also manages the resources required for networking, memory, and processing within NFVI. This component enables efficient resource allocation and ensures that network services can be deployed quickly and effectively.

6. Operation Support System/Business Support System (OSS/BSS)

Commonly referred to as OSS/BSS, this component deals with the operational side of network management. The Operational Support System (OSS) handles configuration, fault detection, and service management. The Business Support System (BSS) focuses on managing customer orders, billing, and product offerings. Together, OSS and BSS ensure smooth operation and customer service in the NFV environment.

7. Virtualised Infrastructure Manager (VIM)

The Virtualised Infrastructure Manager (VIM) manages NFVI resources such as computing, storage, and networking. It optimises the lifecycle of both virtual and physical resources, allowing network operators to maintain operations and deploy new services efficiently. A VIM can either manage multiple NFVI resources or focus on specific aspects as needed.

Benefits of Network Functions Virtualisation

NFV offers numerous advantages that can significantly improve how organisations manage their networks. By separating network functions from dedicated hardware, NFV allows for more efficient and flexible network operations. Here are the key benefits of Network Function Virtualisation:

Cost reduction

NFV helps reduce costs in several ways:

• Less hardware: With NFV, you need fewer physical devices because multiple virtual machines can run on a single server. This decreases the need to purchase and maintain dedicated hardware.
• Lower power consumption: By using fewer physical devices, NFV reduces the power required to operate your network, which can lead to lower utility bills.
• Extended hardware lifespan: NFV can help extend the life cycle of existing network hardware, giving you better returns on your investments.

Faster deployment

NFV accelerates the release of new services, applications, and upgrades. With virtual networks, you can automate the deployment of new features and applications. This automation is part of a process called continuous deployment, where updates become available to users as soon as they pass predefined tests. This speed helps your organisation respond more quickly to market demands.

Lower day-to-day costs

By shifting from specialised hardware to general-purpose servers, NFV lowers both capital expenditures (CAPEX) and operational expenditures (OPEX). These reductions come from fewer hardware purchases, decreased maintenance needs, and the efficiencies gained from automation. Additionally, lower energy consumption further cuts down costs.

Enhanced scalability

One of the standout benefits of NFV is its scalability. As your organisation grows, you can easily scale your network without needing to buy additional physical hardware. Virtual machines can be provisioned (set up) quickly and remotely, making it easier to adapt to changing business needs. This agility allows you to implement network upgrades without the lengthy processes associated with physical devices.

Improved performance

NFV allows for dynamic resource allocation, meaning you can adjust network functions based on current demand. To give you an example of network virtualisation, during high-traffic periods, you can upscale resources to handle the increased load without over-provisioning. This balance helps maintain network performance and reliability, ensuring a better experience for users.

Innovation on-demand

With NFV, organisations can launch, update, or retire network functions and services much more quickly. This flexibility allows you to test new services and respond to customer needs rapidly. The shift to virtual infrastructure means that you can deploy services without the delays often associated with physical hardware changes.

Simplified management

Managing a virtualised network is generally simpler than managing traditional hardware. With NFV, you can control your network functions through software, reducing the complexity associated with configuring and connecting various hardware devices. This simplicity can free up your IT team to focus on more strategic tasks rather than routine maintenance.

How Network Functions Virtualisation works?

NFV operates by replacing traditional hardware networking components with software applications running on virtual machines. In a conventional setup, specific devices like routers and firewalls handle distinct tasks. NFV transforms these functions into software solutions that run on generic servers, enabling the same capabilities—such as traffic routing and security—without the need for dedicated hardware.

Central to NFV is the hypervisor, which allows multiple virtual machines to share the resources of a single physical server. This virtualisation layer manages the allocation of resources and ensures efficient communication between the virtual machines.

Additionally, a Network Functions Virtualisation (NFV) with a touch of SDN (Software-Defined Networking) controller provides centralised management of the network. It enables network engineers to program and automate various network functions, allowing for quick adjustments and streamlined operations.

Network Functions Virtualisation vs. Traditional Network Architectures

Here's a table comparing Network Functions Virtualisation (NFV) with Traditional Network Architectures:

Feature	Network Functions Virtualisation (NFV)	Hardware
Hardware	Utilises general-purpose hardware (e.g., standard servers)	Relies on dedicated hardware devices
Software-hardware decoupling	Software is separate from hardware, allowing modular updates	Software is tightly coupled with specific hardware
Openness	Promotes an open ecosystem, facilitating multi-party collaboration	This often leads to closed systems, limiting third-party integration
Network flexibility	Allows dynamic resource allocation and adjustment based on demand	Rigid resource allocation; harder to adapt
Upgrade convenience	Fast upgrades, primarily through software changes	Time-consuming upgrades involving both software and hardware
Automated operations	More automated and intelligent management of resources	Manual processes for maintenance and upgrades
Service association	Services can be flexibly orchestrated and deployed	Service requirements are more rigid and slower to adapt

Implementing Network Functions Virtualisation in your network

Implementing NFV in your network involves several essential steps to ensure a successful transition from traditional networking. These include:

1. Create and deploy virtualised network functions

VNFs are software-based versions of traditional networking equipment, such as routers and firewalls. It’s important to build these VNFs strategically and in sequence as part of a service chain. This method allows you to deliver more complex products and services effectively.

2. Set up the orchestration layer

Next, establish the orchestration layer. This layer is responsible for several critical tasks, including:

• Deploying VNFs
• Monitoring their performance
• Repairing any issues that arise
• Billing for their usage

By implementing carrier-grade features in your orchestration layer, you can ensure that your services are highly scalable and reliable. This will help reduce operational and maintenance costs while providing high availability and security.

Moreover, make sure your orchestration layer can manage VNFs independently from the underlying hardware. This means it should work with any VNF from any vendor, regardless of the technology used.

3. Utilise reliable servers

Your NFV setup will rely on reliable, high-performance servers. These servers are crucial for hosting the VNFs and ensuring they operate effectively.

You can choose from several virtualisation technologies for your NFV architecture, such as:

• VMware: A widely used hypervisor that allows multiple virtual machines to run on a single physical server.
• OpenStack: An open-source platform that provides tools to manage and automate cloud services.
• Container technology: While still emerging, it offers significant benefits for application performance by packaging applications and their dependencies together.

4. Customise the MANO layer

The Management and Orchestration (MANO) layer is vital for NFV implementation. This layer can be either open-standard or vendor-specific. Plus, you’ll need to customise the MANO layer to fit the specific requirements of your network operations and billing systems. This customisation ensures that the NFV framework aligns with your existing processes and enhances your overall network management.

5. Enable full-featured applications

At the application layer, VNFs provide full-featured network application code. In more advanced setups, you can select multiple VNFs to create a service chain, allowing for extensive network functionality.

Typical applications of NFV include:

• Mobile networks: Supporting mobile data and voice services.
• Content Delivery Networks (CDN): Enhancing video streaming and content distribution.
• Network slicing: Creating virtual networks tailored for specific services.
• Software Defined Wide Area Networks (SD-WAN): Improving network management across multiple locations.

Best practices for Network Functions Virtualisation deployment

When deploying Network Functions Virtualisation (NFV), it’s crucial to adopt best practices to ensure a secure and efficient environment. Here are key considerations to keep in mind:

Use strong encryption and authentication

• Encryption: Encrypt your data wherever it is stored, transmitted, or used. This protects sensitive information from unauthorised access. Look for encryption tools that offer both inband (within the data stream) and out-of-band (separate from the data stream) management for added security.
• Key management: Manage your encryption keys carefully. If keys are lost or stolen, your data could be compromised. Use centralised and secure key storage solutions to ensure that your encryption keys remain safe.
• Access controls: Implement strong access controls to ensure only authorised users can access your systems. Use multi-factor authentication, which requires users to provide two or more verification factors to gain access, to strengthen security.

Adopt a holistic security approach

Security in NFV requires more than one solution. Combine hardware and software-based security measures to create a comprehensive defence. Keep up with emerging standards in the NFV domain to ensure your systems can work together seamlessly.

Profile your environment and assets

Understanding your environment is crucial for effective security:

• Data: Identify all types of data in your organisation, especially sensitive information like personal identification or payment card data. Evaluate how long this data is useful and the risks associated with it.
• Traffic: Monitor data flow connections between devices and applications. Knowing how data moves through your network helps you set up necessary controls.
• Hardware: Even in virtualised environments, physical hardware is still relevant. Know who owns each piece of hardware, where it is hosted, and how it is protected. Clearly define data ownership, especially when working with multiple vendors.

Ensure scalability

As your organisation grows, so will the demands on your security systems. Ensure that your security solutions can scale to handle increased numbers of users, devices, and data connections. This includes the ability to support more authentication requests as your network expands.

Prepare for disasters

Develop a disaster recovery plan for both natural disasters and security breaches. Identify your most critical assets and create strategies to protect them. Implement multi-layer security measures, such as data encryption, to safeguard your NFV network.

Clarify roles with third parties

Most organisations use a mix of internal resources and external services. Make sure you understand the security responsibilities of each partner. Investigate their security practices to ensure they align with your organisation’s needs. It’s important to keep control over critical aspects, such as encryption keys, especially when data is shared externally.

Conduct thorough vendor research

Investing in NFV may require purchasing new security solutions. When choosing vendors, consider the following:

• Core competency: Is the security solution a core part of the vendor's expertise?
• Track record: Does the vendor have a strong history of successful implementations?
• Support staff: Are there qualified personnel available to help you implement and maintain the solution?

Test solutions before implementation

Before deploying a new solution, conduct thorough testing. Assess how the system performs under various conditions, such as failures in the network. Monitor important factors like response time and overall performance to ensure the solution meets your needs.

Common challenges and solutions

Implementing Network Functions Virtualisation (NFV) comes with several challenges that service providers must navigate. Here are some common challenges and practical solutions:

• Legacy infrastructure compatibility: Many existing networks rely on proprietary (custom-made) hardware and software, which may not easily support NFV. To overcome this, conduct thorough planning and integration efforts to ensure that legacy systems can work with new NFV technologies. This may involve updating some hardware and software components.

• Performance and scalability issues: Virtualised networks can face challenges in maintaining low latency (minimal delays), high throughput (data transfer rates), and reliability. To address this, optimise the Virtual Network Functions (VNFs) by monitoring performance regularly and adjusting resource allocation to meet demand during peak times.

• Security risks: NFV environments are more vulnerable to security threats, such as malware and hacking, due to their virtual nature. Implement stringent security measures tailored to virtual environments. Use advanced monitoring tools to detect unusual activities and ensure regular updates to security protocols.

• Complexity in orchestration and management: Managing multiple virtualised VNFs requires advanced orchestration (the coordination of various services) tools. Simplify management by using integrated platforms that provide a single interface for monitoring and managing resources, allowing for easier troubleshooting and resource allocation.

• Interoperability and standardisation challenges: NFV relies on various vendors for hardware and software, which can lead to compatibility issues. Promote the use of open standards and interfaces to facilitate better integration among different vendors. This approach can minimise disruptions and enhance cooperation.

• Skill gap and training needs: The transition to NFV requires knowledge of virtualisation, networking, and cloud computing. To bridge this gap, invest in training programs for network operators. Building these skills will ensure a smoother adoption of NFV technologies and improve overall efficiency.

Future trends in Network Functions Virtualisation

Some trends that will help you leverage NFV effectively for improved network performance and flexibility are:

Edge computing integration

As the need for fast, low-latency applications grows, integrating NFV with edge computing becomes crucial. Deploying virtualised network functions closer to users reduces delays in data transmission. This setup enhances user experiences and enables innovative applications like augmented reality and real-time data analytics.

Synergy with 5G networks

The rollout of 5G technology is transforming internet infrastructure, and NFV plays a key role in this transition. NFV supports dynamic resource allocation, ensuring the network meets 5G’s demands for high data speeds and low latency. This collaboration sets the stage for advanced connected technologies.

Machine Learning and automation

Combining NFV with Machine Learning (ML) and automation streamlines network management. Intelligent algorithms analyse data patterns and predict network demands, allowing for automated resource allocation. This not only improves network performance but also cuts operational costs and boosts overall efficiency.

Containerisation in NFV

Containerisation technologies, such as Docker and Kubernetes, are gaining popularity within NFV. These containers are lightweight and portable, making it easier to package and deploy virtualised network functions. This trend enhances resource efficiency and accelerates the launch of new services, reflecting a shift toward more agile network management.

Open-source contributions

Open-source projects like OpenStack, ONAP (Open Network Automation Platform), and OPNFV (Open Platform for NFV) are vital to NFV’s evolution. These initiatives encourage collaboration and standardisation in developing NFV solutions. Contributions from the open-source community drive innovation and ensure that NFV can be adopted widely across different network setups.

Enhanced security measures

As virtualised networks grow more complex, ensuring robust security is essential. There is an increasing focus on integrating security functions within NFV architectures. This includes using virtualised security appliances and adopting zero-trust security models, which verify users and devices before granting access. Protecting critical network infrastructure from cyber threats is vital.

Cloud Connectivity with SD-WAN, SDN, and NFV

SD-WAN, SDN, and NFV are transforming how businesses manage their networks, particularly when it comes to optimising cloud connectivity. SD-WAN (Software-Defined Wide Area Network) enhances the flexibility and efficiency of connecting branch offices to the cloud by intelligently routing traffic across the best available links. SDN (Software-Defined Networking) enables centralised control over the network, making it more adaptable and responsive. NFV (Network Functions Virtualisation) allows network services like firewalls or load balancers to be virtualised, reducing the need for hardware.

Together, these technologies streamline the creation of hybrid and multi-cloud architectures. By using network virtualisation, businesses can interconnect multiple clouds more seamlessly, enabling better performance, faster deployment, and improved cost efficiency. As enterprises move toward a multi-cloud strategy, the combination of SD-WAN, SDN, and NFV becomes crucial for ensuring that network performance scales with the growing demands of the cloud

Conclusion

Network Functions Virtualisation holds significant potential for transforming network architecture, particularly in the context of Network Function Virtualisation in 5G. However, it also faces key challenges that need to be addressed. Ensuring compatibility with legacy systems, enhancing the performance and scalability of virtualised network functions, and tackling security concerns are critical steps for successful implementation.

Additionally, managing complexity, promoting interoperability and standardisation, and maintaining performance assurance are essential for maximising the benefits of Network Function Virtualisation. Moreover, bridging the skill gap through education will be important for effectively integrating Network Functions Virtualisation (NFV) with a touch of SDN. For more information, Contact us today.