How Cloud-Native Functions (CNFs) will be the foundation to 5G

June 25, 2020

Container networking is part of an evolution that began over a decade ago with network virtualization that provides lots of benefits to telecom operators around cost, speed and ease of development compared with physical networks.

With virtualization, hardware resources are shared by Virtual Machines (VM), each of which includes both an application and a complete operating system instance. A physical server running multiple VMs, would, for example, feature a hypervisor accompanied by multiple separate operating systems running on top. So, this meant that network agility and flexibility was limited.

On the other hand, a server supporting multiple containerized applications requires just a single operating system, with each container sharing the operating system kernel with its companion containers. While a VM with its own operating system may consume several gigabytes of storage space, a container might only be tens of megabytes in size. Therefore, a single server can host many more containers than VMs, significantly boosting data-center efficiency while reducing equipment, maintenance, power, and other costs.

vm Containers

When comparing CNFs to VMs, there are a number of similarities. However, CNFs are the evolution of VMs. Containers or Cloud-Native Network Functions (CNF) are a standalone lightweight node which includes everything they need to run, such as, code, libraries, system tools, and frameworks. They are able to share and receive data from the host more efficiently, which compares favorably with some of the complex functions present in VMs and VM orchestration. Built using a microservices architecture, they are dynamic, flexible, and easily scaled, making them a favored solution in the transition to 5G.

Through this blog, we will look at this evolution and examine some of the benefits that containerization and cloud-native network offer.

Benefits of deploying CNFs

CNFs are built using a microservices architecture, which provides the operator with many benefits when running their cloud network. Their microservices architecture means that each CNF is comprised of small independent processes or elements which all communicate with each other and enable a modular approach to system building. Consider a CNF as version 1.0 of new software. It is clean and works perfectly. Over time there will be updates and additions, making it more complicated and more cumbersome. A microservices architecture means the CNF is built-in parts, almost a Lego-like structure, removing and adding pieces as needed, keeping it lightweight and agile.

1. Efficient scaling

The CNF enables the deployment of network functions which are automated and are controlled with high levels of granularity, meaning it is possible to spin up services with greater precision as well as efficiency. This type of scaling will be critical as services become more dynamic and delivered on-demand.

CNFs are agile and flexible and can respond to changes in the network as and when instead of having to predict trends and react to them. Thanks to the lightweight nature, they can be instantiated in a matter of seconds compared to the minutes it takes to start a VM, meaning operators can respond to changes on-the-fly, which is essential in the ever-changing 5G environment.

2. Ease of deployment

Perhaps the most exciting development is with Continuous Integration/ Continuous Deployment (CI/CD). No matter what the application, with a CNF, the process of deployment is greatly simplified. This means any new development to the container can be integrated and deployed in a matter of seconds, enabling quick improvements and updates to the network. Moving to cloud-based software development will allow operators to innovate and launch new services quickly.  

3. Smooth orchestration and interoperability

Despite their infancy, CNFs are viewed to have fewer management and configuration requirements, meaning they can easily be incorporated into public clouds as well as into an operator’s private cloud environment. Several orchestration solutions have been developed, with Kubernetes (K8) by Google, perhaps the most advanced. Kubernetes controls the container-based functions, which enables automation in the network. Operators will face the challenge of figuring out how Kubernetes and containers fit into their existing network and deliver on the required end-to-end visibility. However, once they overcome these challenges, they will have a software-controlled network that is dynamic and can provide the agility needed for advanced 5G services.    

4. Delivers a fully cloud-native network

The Standalone 5G core network will be built using a microservices architecture and containerized functions. This means the network is able to grow on-demand to cope with the complex new use cases as well as the growth in demand for network capacity. Rakuten CTO, Tariq Amin explained the transition in a recent article, where he stated, “We will take the 5G core, once built with all containerized functions and components, (we) will collapse all of the 4G functions, and is probably 14 to 16 months we are anticipating we will have one single converged core 100% pure cloud-native function on Rakuten Communications Platform.” This example shows how CNF’s will play a critical role in the smooth transition from 4G to 5G networks and enable companies to innovate while saving costs rapidly.

All of these benefits are useful in and of themselves. However, the underlying value of CNFs is in their ability to help deliver flexibility, scalability, and automation in 5G. These are critical values for next-generation service assurance solutions.

Containerization and Service Assurance

One of the main challenges for operators in their transition to 5G is the management of both legacy and cloud-native components. This hybrid architecture will consist of a mix of Physical Network Functions (PNFs), CNFs, and VMs. In short, to medium term, it is expected that many of the deployments on the road to 5G will have hybrid elements to them. Operators will have the complex task of monitoring differing iterations of the network and their functions. It is, therefore, important that service assurance offers operators the ability to deliver end-to-end network visibility in a hybrid environment as well as having the ability to deploy components either as CNFs, VMs, or any mix of them.

Transitioning to a container-based assurance solution will allow it to be integrated seamlessly into an operators’ network, be dynamic, elastic, easy to scale, and enable an automated closed-loop environment. CNFs enable service assurance to deliver many of the requirements an operator needs when monitoring their 5G network and providing that end-to-end visibility from the RAN to the Core.

To effectively monitor and manage the increase in traffic that 5G will present, service assurance will need to correlate the data to deliver real-time insights smartly. A container-based approach will allow a service assurance solution to dynamically respond to changes in the network, managing the network capacity automatically. Additionally, if one container were to fail, it would not have as severe an impact on the rest of the network as the issue can be isolated and repaired, providing greater resiliency in the network. Similarly, when an element becomes redundant or fails, the system “fails back” to the back-up component. Previously this process would have taken some time and would have resulted in a loss of service. However, with a containerized solution, failback is performed rapidly, meaning minimal interruption to the end-user.

Furthermore, a cloud-native service assurance solution is centrally managed using Kubernetes. This enables operators to automate the deployment, scaling, and management of all containerized functions, delivering a unified view of the network. The microservices architecture also allows the operator to incrementally update Pods instances with new ones, known as a rolling upgrade. This will enable deployments to take place with zero downtime. Due to its Lego-like structure, individual elements can be changed or updated without affecting the entire CNF.

In addition to this, 5G will also present many new advanced use cases, one of which will be network slicing. This will enable operators to deliver complex requirements to one set of subscribers using one slice of the network, and completely different requirements to another slice. Examples of this could include ensuring ultra-low reliable latency for autonomous vehicles for real-time feedback and reactions, or super-fast downloads for gamers. Network slicing can be highly dynamic and scaled up and down depending on the capacity needed at that time. Equally, service assurance will need to react to these needs to ensure Service Level Agreements are met, and the Quality of Experience remains high. To achieve this, CNFs will be a crucial component in assuring these advanced services. 

RADCOM Service Assurance is a fully automated and containerized solution for 5G. The combined solution is a dynamic multi-functional solution that unifies both the frontend and backend into a single node.  To learn more about RADCOM Service Assurance solution for intelligent, containerized, on-demand, network analysis, and how it delivers full network visibility from the RAN to the core click here.

This blog post may contain forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. To read more about forward-looking statements, please click here.

Share this article
Skip to content