O-RAN: Analysis of Latency-critical Interfaces and Overview of Time Sensitive Networking Solutions
arXiv:2607.27448 · doi:10.1109/MCOMSTD.0001.2200041
The paper reviews latency‑critical O‑RAN interfaces and examines how Time Sensitive Networking (TSN) standards can provide deterministic performance over cost‑effective Ethernet transport for virtualized RAN deployments.
Abstract
5G and B5G/6G foundations heavily rely on virtualization technologies, and virtualized Radio Access Networks (vRANs) are one of their major keystones. However, while vRANs have been traditionally suffering from significant hardware/software coupling, next generation vRANs aim for open, standardized interfaces and multi-vendor, interoperable components to enable truly flexible deployments following the cloud-native principles. In this line, the O-RAN Alliance is promoting a novel Open RAN architecture to further boost flexibility and cost efficiency. In order to reduce costs and effectively achieve the promised disaggregation levels, O-RAN must ensure shared, integrated transport networks in opposition to dedicated, over-provisioned links from traditional approaches. However, keeping deterministic performance requirements in such cost-effective networks (i.e., general-purpose Ethernet networks), especially in those interfaces that are time-critical, is a challenge. In this article, we review the most relevant Time Sensitive Networking (TSN) standards that may bring compelling benefits to O-RAN (i.e., IEEE 802.1CM, IEEE 802.1Qbu and IEEE 802.1Qbv) for providing determinism over cost-efficient networks. We explore the design space for a TSN-enabled O-RAN architecture, reporting on the requirements and deployment options and finally, we discuss on the opportunities and challenges that O-RAN will face when adopting TSN technologies to fully open the vRAN ecosystem.
8 pages, 4 figures. Published in IEEE Communications Standards Magazine on October 2023