How SONiC Is Powering Open Optical Networking: First Large‑Scale Deployment and the New OTN Working Group

As a critical carrier of the digital economy, information networks are entering a new era driven by cloud computing, artificial intelligence, big data, and the Internet of Things, which bring unprecedented scale as well as significant challenges; openness and open‑source are seen as key technologies to address these challenges.

SONiC (Software for Open Networking in the Cloud) was launched in 2016 as a Linux‑based open‑source network operating system. Backed by leaders such as Microsoft and Alibaba, it has been widely adopted in the networking field, notably in Alibaba Cloud's self‑developed white‑box switches deployed across data centers.

Two years ago Alibaba Cloud began exploring SONiC for optical networks in its data‑center fabric. The effort resulted in the first industry‑wide development of a SONiC‑based white‑box optical transport device, which has since been deployed at scale. The achievement was presented at the ECOC conference in Basel, Switzerland, in September 2022.

Following the deployment, Alibaba Cloud actively promoted the technology as open source. At the SONiC Technical Steering Committee (TSC) meeting on 10 November 2022, Alibaba Cloud delivered a report on optical networking with SONiC and recommended that the TSC incorporate optical transport networking into the SONiC roadmap.

On 8 December 2022 the SONiC‑OTN (Optical Transport Networking) working group was officially approved by the SONiC TSC. The group is co‑chaired by Dr. Xie Chongjin from Alibaba Cloud and Dr. Yin Yawei from Microsoft.

The working group’s initial objectives, announced at its kickoff on 18 January 2023, are to enable SONiC support for three categories of optical transport equipment:

Terminal optical transceivers (Tx/Rx modules).

Optical line equipment such as amplifiers and wavelength‑selective switches (WSS).

Pluggable DWDM or gray‑light modules for switches/routers.

These goals are slated for completion within two years.

The kickoff meeting, held online, gathered participants from Alibaba Cloud, Microsoft, Kuaishou, NTT, Cisco, Infinera, and others. Both Alibaba Cloud and Microsoft presented their previous work on SONiC for OTN and SONiC support for 400ZR, respectively.

Through the SONiC‑OTN working group, the community aims to advance open‑source optical networking, accelerating the development and adoption of optical transport technologies.