Shift from On-prem to Cloud Networking Environments with CNFs


This submit is the primary in a collection across the Cloud-Native Community Perform Orchestrator (CNFO).

Half 1: What are CNFs?

Earlier than we dig into the Cloud-Native Community Perform Orchestrator (CNFO), let’s begin with Cloud-Native Community Capabilities (CNFs).

The naked bones definition of a CNF is a container which is working a community perform, akin to a firewall or VPN. Contextually, CNFs are the following stage of an evolution that started with bodily gadgets, progressed to digital community capabilities (VNFs), and is now heading in the direction of CNFs. As evident within the identify, “Cloud-Native” Community Capabilities finally characterize a shift from on-premises environments in the direction of cloud-based networking environments.

Bodily Gadgets

Bodily gadgets, like routers or switches, are monolithic and goal constructed, which means that they run on devoted {hardware} and home all their very own purposes. Whereas devoted bodily {hardware} have their boons, they solely carry out one job (i.e. be a router). Consequently, bodily gadgets are costly as constructing out scale and redundancy requires investing in additional {hardware}. If {hardware} goes down, engineers should spend time and assets troubleshooting the machine. Community engineers noticed a option to take away devoted {hardware} dependency by implementing digital community capabilities (VNFs).

Digital Community Capabilities

By shifting to VNFs, community engineers began breaking community performance into smaller items. Engineers might rack a generic piece of {hardware} after which run a hypervisor, which permits the working system to run a number of digital machines. Every digital machine runs a VNF. One VNF may home a VPN gateway whereas one other might run a firewall. Segmenting community performance and eradicating {hardware} reliance made constructing scalability and redundancy cheaper. Along with value financial savings, VNFs have been a pure first step, as they’re architecturally and operationally just like bodily networks.

In apply, VNFs fall in need of their preliminary guarantees. VMs are taxing on assets, have lengthy boot up instances, and, typically instances, sit idle. Most notably, VNFs resemble bodily gadgets in that they’re constructed as monolithic, single-purpose digital purposes. VNFs have began the networking world on its journey to the cloud, however fall in need of making the ultimate leap.

Cloud-Native Community Capabilities

CNFs characterize the following step into cloud-based environments. CNFs break monolithic VNF purposes into particular person parts. A number of containers work collectively inside a cluster to create the general community perform.  Every cluster is managed by a Kubernetes-like lifecycle supervisor, akin to fundamental Kubernetes, Openshift, or EKS.

Since CNFs are composed of particular person, light-weight containers, they’re straightforward to spin up or down, which has a cascade of implications. CNFs are able to self-healing: if a person container fails, it’s simply and rapidly changed. Engineers don’t must troubleshoot like they might a VNF or bodily machine. As well as, CNFs can run on personal servers or on the general public cloud, which reduces the necessity for {hardware} funding.

Nevertheless, this final bounce into the cloud will in all probability be the largest bounce. With the shift to the cloud comes the merging of two established fields, DevOps and Community Engineering (coined NetDevOps). Proper now, there’s a technological and cultural hole as community engineers study to be builders and vice versa.


A part of what we’re making an attempt to do with CNFO is assist bridge the hole between the cloud and the present networking world. As such, I need to hear from you. Are you accustomed to CNFs or are they solely new? How do you see your self utilizing them? Let me know your ideas within the feedback and when you’d like to attach.

To be clear, we don’t suppose that bodily gadgets or VNFs are going away solely. Moderately, community engineers might want to orchestrate a discipline composed of all three community perform sorts. Fortunately, orchestrating throughout machine sorts and at massive scales is the place NSO excels. We’ll dig into how NSO can orchestrate CNFs (in addition to VNFs) in Half 2 of this weblog collection.

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