DPDK-Accelerated O-RAN DU With Per-Flow Network Slicing and 3GPP-Compliant Dynamic Bandwidth Guarantee

Abstract

Open Radio Access Network (O-RAN) disaggregates the traditional base station into the Radio Unit (RU), Distributed Unit (DU), and Central Unit (CU) with standardized open interfaces, enabling multi-vendor interoperability and reducing deployment costs. However, realizing per-flow network slicing at the DU while simultaneously meeting the high-throughput demands of 5G remains a significant challenge. This paper presents DPDK-DU-NS, a DPDK-enabled O-RAN DU that supports per-flow network slicing and bandwidth management in compliance with 3GPP 5G QoS flow and bearer management specifications. DPDK-DU-NS separates the control plane and user plane of an OpenAirInterface (OAI)-based DU and offloads user plane functions to Intel DPDK to achieve high-speed packet processing. We further propose Adaptive Metering, a dynamic bandwidth allocation mechanism that provides Guaranteed Bit Rate (GBR) service while fairly distributing residual capacity among active QoS flows, leveraging the Two-Rate Three-Color Marker (trTCM) algorithm. Experimental results demonstrate that the system enforces 3GPP-compliant per-flow bandwidth guarantees and limits with near-perfect fairness, ensuring robust network slice isolation. These findings, coupled with the achieved 10 Gbps line-rate throughput, validate the DPDK-DU-NS user plane as a high-performance and scalable foundation for next-generation O-RAN DU implementations.