Shift from On-prem to Cloud Networking Environments with CNFs



This publish is the primary in a sequence 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 operate, equivalent to a firewall or VPN. Contextually, CNFs are the subsequent stage of an evolution that started with bodily gadgets, progressed to digital community features (VNFs), and is now heading in the direction of CNFs. As evident within the identify, “Cloud-Native” Community Capabilities finally symbolize 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 objective constructed, which means that they run on devoted {hardware} and home all their very own functions. 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 method to take away devoted {hardware} dependency by implementing digital community features (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 would possibly 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 price financial savings, VNFs had been a pure first step, as they’re architecturally and operationally much like bodily networks.

In follow, 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 functions. 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 symbolize the subsequent step into cloud-based environments. CNFs break monolithic VNF functions into particular person parts. A number of containers work collectively within a cluster to create the general community operate.  Every cluster is managed by a Kubernetes-like lifecycle supervisor, equivalent 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 shortly changed. Engineers don’t must troubleshoot like they’d a VNF or bodily machine. As well as, CNFs can run on non-public servers or on the general public cloud, which reduces the necessity for {hardware} funding.

Nonetheless, this final soar into the cloud will most likely be the most important soar. 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 be taught 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 prevailing networking world. As such, I wish to hear from you. Are you accustomed to CNFs or are they fully new? How do you see your self utilizing them? Let me know your ideas within the feedback and in case you’d like to attach.

To be clear, we don’t assume that bodily gadgets or VNFs are going away fully. Moderately, community engineers might want to orchestrate a area composed of all three community operate varieties. Fortunately, orchestrating throughout machine varieties and at giant 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 sequence.

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