The road to containerized network functions

【51CTO.com Quick Translation】Service providers and enterprises are making extensive use of containers and microservices in today’s cloud-based applications. They want to do the same with universal CPE (uCPE) deployed at the edge using network function virtualization (NFV).

However, one of the limitations of NFV today is the use of monolithic virtual network functions (VNFs) running in virtual machines. Users want to be consistent with what they do in the data center cloud, which means taking a cloud-native approach to implementing VNFs. This means breaking down the monolithic architecture into a microservices architecture and implementing it into containers.

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It’s an ambitious goal, but the technology isn’t there yet. With a few rare exceptions, today’s VNFs are implemented as monolithic systems running in virtual machines, but that’s OK! Today, there are many solutions that support both VMs and containers, so there’s no reason to wait to deploy NFV-based services.

The right platform drives innovation

Today’s VNFs are suitable for immediate deployment of dynamic and cost-effective services. They provide a seamless transition from hardware appliances to virtualized solutions. If you choose the right platform, you can gracefully migrate to newly available containerized network functions (CNFs). Several CNFs already implement features such as encryption and test agents, which can coexist with VNFs.

Will virtual machines disappear?

There is no reason to think that virtual machines will disappear. Containers and virtual machines can exist in a complementary relationship, as shown in the following figure.

The advantages of containers are that they take up less memory and disk space and start faster. In addition, they enable microservices architecture.

But virtual machines offer more effective isolation in terms of security and dependency on the underlying operating system. In addition, VNF implementations in virtual machines are commonplace and they will be around for a long time.

So we need both VMs and containers, and the right platform supports both. In fact, we see a big reason why VMs and containers coexist today.

Let's take the example of a carrier wanting to use containers for managed services for certain network functions. Let's also assume that the end user wants to be able to run their own containerized functions. I've talked to a number of carriers who claim to use VMs to isolate the end user's containerized applications. This would separate the end user applications from the applications that the carrier runs directly on the platform.

At the end of the day, both VMs and containers are important. You can start with VMs today and migrate to them in the future without having to change your host hardware.

But what about network performance?

CNFs have advantages over VMs in terms of size and boot time. However, I have seen similar network performance in my testing. Both VNFs and CNFs can use technologies such as the Data Plane Development Kit (DPDK) and accelerated vSwitch to provide carrier-grade performance.

Don't wait, start now!

If you have a platform that is future-proof, there is no need to wait. You can start with a wide range of VNFs today and mix containerized applications as needed. Later you can migrate from VNFs to CNFs without upgrading hardware.

Original title: The Road to Containerized Network Functions, Author: Prayson Pate

[Translated by 51CTO. Please indicate the original translator and source as 51CTO.com when reprinting on partner sites]