ONF Releases SD-RAN v1.0 for Open RAN

January 26, 2021

The ONF made a major milestone for the SD-RAN open RAN project with its first software release. SD-RAN v1.0 is a cloud-native exemplar platform for software-defined RAN that is consistent with the O-RAN architecture.

Background
Carriers globally are looking to open RAN as a way to enable modular and customizable 5G solutions that avoid vendor lock-in and enable the mix-and-match of vendors’ components while accelerating the ability to innovate and add new functionality, and a number of organizations are collaborating in the pursuit of this goal. The O-RAN Alliance is defining this open architecture, TIP’s OpenRAN RIA subgroup is defining requirements for AI/ML use cases, and the ONF’s SD-RAN project is building an open source implementation that is consistent with this architecture to help foster innovation and speed the development and availability of production-grade open RAN solutions. SD-RAN is also an integral part of ONF’s Aether connected edge cloud platform, bringing the power of open RAN to private enterprise 5G/LTE edge applications.

The SD-RAN community includes leading operators, vendors and other connectivity stakeholders embracing the open RAN movement and the vision of a vendor agnostic nRT-RIC to help enable multi-vendor interoperability. Current SD-RAN community members include: Aarna Networks, Airhop Communications, AT&T, China Mobile, China Unicom, Cohere Technologies, Deutsche Telekom, Facebook, Google, Intel, NTT, Parallel Wireless, Radisys and Sercomm.

The ONF’s first release of the SD-RAN project implements a minimal O-RAN consistent end-to-end mobile RAN stack intended as a development environment for building xApps for the emerging Open RAN ecosystem. It includes µONOS-RIC (ONF’s nRT-RIC based on µONOS) which interacts with RAN hardware (RU/DU/CU) via O-RAN consistent interfaces (E2AP), encodings (ASN.1), transport-protocols (SCTP) and Service Models (SMs). The release also includes a white-box based RU/DU/CU solution, leveraging OAI software, that has been enhanced to expose O-RAN consistent interfaces and protocols. To integrate with µONOS-RIC, the CU-CP RAN component has been enhanced with an E2 Agent that exposes the KPM-SM information-elements to xApps that connect to the nRT-RIC and subscribe to the KPM service. image png

Secondly, an end-to-end solution is provided. The RAN components interact with Samsung Android handsets as well as OAI User Element (UE) emulation software. For mobile core (EPC) integration, the RAN components interact with ONF’s OMEC mobile core.

This release also includes the beginnings of an app-SDK which can ease the process of creating xApps that are portable across different nRT-RIC platforms. As part of ONF’s commitment to supporting the O-RAN Alliance, this SDK is being shared with the O-RAN Software Community to support and promote availability of interoperable xApps and rApps that can work with a selection of nRT-RIC implementations.

Finally, the solution can be instantiated in two distinct forms to create nimble development environments. SD-RAN can run on reference white-box hardware, and it can also be instantiated entirely in a virtualized form (in a VM or server) in a distribution package called RiaB (sdRan-in-a-Box). The entire distribution including xApp, µONOS-RIC components, CU/DU, UE and OMEC can be instantiated within RiaB with just a few simple commands.

Taken together, this is the start of a complete development environment for xApp developers and for those wishing to integrate RU, DU and CU RAN components into an open RAN solution. This will enable vendors to begin to enhance their components to work with an O-RAN consistent solution, setting the stage for building and trialing multi-vendor open RAN solutions.