As telecom carriers continue to build out data centers supporting ever faster speeds, there is a key role that the open source SONiC (Software for Open Networking in the Cloud) network operating system (NOS) can play.

At a session at the Nvidia GPU Technology Conference (GTC), experts from Nvidia and Comcast outlined how and where the open source NOS can fit in to support 400 gigabit Ethernet deployment. Comcast is using the open Ethernet approach to meet requirements in seven of its national data centers and in smaller builds across 25 deployments inside of carrier neutral facilities. Included in the deployment are the use of SONiC enabled Nvidia SN4700 networking switches that support 32 ports of 400G. Nvidia's networking division got started in earnest as part of the company's $6.9 billion acquisition of Mellanox Technologies in 2019.

David Iles, senior director of Ethernet Switching at Nvidia, said that network operators are generally looking to simplify and automate operations. Part of that process is having the capability to run the same protocol across the network and not be locked into one vendor's specific NOS software. That's where SONiC fits in as a vendor-neutral open source network operating system. SONiC was originally built by Microsoft and formally became an open source project in 2015 when it joined the Open Compute Project (OCP). In 2022, the project moved to its current home at the Linux Foundation.

"SONiC is really the leading open source community network operating system for data centers for clouds," Iles said. "It's modular and containerized and  basically built from the ground up to be scalable for large network deployments."

Part of the attraction of SONiC, is the integration of the Switch Abstraction Interface (SAI), which provides a vendor-neutral approach of controlling switches in a standardized model.

With SAI, Iles said that it's easier for operators to manage, configure, and scale switch deployments.

The openness of SONiC is helping to grow the overall ecosystem of usage, with Iles noting that IDC has forecast the SONiC data center switch market to be worth $2 billion by 2024. Gartner has forecast that by 2025, 40% of organizations that operate large data center networks of 200 or more switches will run SONiC in production environments.

During the Nvidia GTC session, Charles Conte, executive director at Comcast detailed about the requirements his organization had to help build out 400G for its deployments.

The exhaustive list of requirements included both business and technical needs such as  low latency, high throughput, high density, interface flexibility and a desire to be able to support both open and commercial network operating systems.

Nvidia's switching gear with SONiC helped to fit the bill for the tier 1 and tier 2 spine in the Comcast national data center deployment as well as being used for packet broker operations.

One of the key reasons why Comcast has embraced SONiC is because fundamentally at its core, it's Linux.

"A lot of people might say they're running Linux, but the OS itself is actually almost just a single application that's just running on Linux versus giving you that full Linux user experience," Conte said. "This is almost like an out of the box experience with SONiC because it is truly is a Linux user experience."

As a native Linux experience, Conte and the Comcast team were able to use existing Linux skills and configuration management tools such as Ansible to help with deployment and administration as well as simplifying instrumentation.

The openness of Linux and the open source community has also been a real help to Conte and Comcast. He recalled there was a situation where Comcast needed some networking packages to be fixed. As it turns out, there was also a competitive vendor (that Conte did not name) that had a similar need and contributed a fix to the upstream open source project.

"SONiC was at bridge point, it was a zero touch provisioning package and it worked like a champ," Conte said. " I was absolutely shocked and  I said, Wow, this is the power of community."