Network Slice as a Service (NSaaS) is a key enabler of Beyond Fifth Generation (5G) and Sixth Generation (6G) networks, supporting next-generation applications such as extended reality (XR), immersive services, and the tactile Internet. These networks must provide native support for slice-aware services across the entire Radio Access Network (RAN), including the Radio Unit (RU), Distributed Unit (DU), Central Unit (CU), and transport segments (fronthaul, midhaul, and backhaul). However, uplink slicing identification in shared Open-RUs (O-RUs) presents a fundamental challenge because the Open-DU (O-DU) handles scheduling, and the O-RU does not inherently know which uplink data belongs to which slice. In MultiPoint-to-MultiPoint (MP2MP) fronthaul scenarios, this limitation is further exacerbated by synchronization and timing constraints, which necessitate that the O-RU process control messages and the encapsulated data be delivered with ultra-low latency. To address this issue, we propose a slicing agent embedded in the O-RU that identifies slices and segregates uplink data into slice-specific enhanced Common Public Radio Interface (eCPRI) packets. Our design employs a pipeline architecture with dedicated paths for time-sensitive, flexible slicing, enabling slice isolation and prioritization. When implemented on an Field-Programmable Gate Array (FPGA), the agent processes each packet in 2 clock cycles, supporting up to 3822 slices per slot. Experimental results validate the approach, showing its feasibility, scalability, and high-performance capabilities for real-time, slice-aware uplink processing in Beyond 5G and 6G Open RAN deployments.

翻译：摘要：网络切片即服务（NSaaS）是第五代（5G）后及第六代（6G）网络的关键使能技术，支持扩展现实（XR）、沉浸式服务和触觉互联网等下一代应用。这些网络需在包括无线电单元（RU）、分布式单元（DU）、中央单元（CU）及传输段（前传、中传、回传）的整个无线接入网（RAN）中，为感知切片的服务提供原生支持。然而，在共享开放无线电单元（O-RU）中，上行链路切片的识别面临根本性挑战：由于开放分布式单元（O-DU）负责调度，O-RU无法天然知晓上行数据归属哪个切片。在多对多（MP2MP）前传场景中，同步与定时约束进一步加剧了这一限制，要求O-RU处理控制消息并以超低延迟交付封装数据。为解决此问题，我们提出一种嵌入O-RU的切片代理，该代理识别切片，并将上行数据隔离至切片特定的增强型通用公共无线电接口（eCPRI）数据包中。我们的设计采用流水线架构，为时间敏感且灵活的切片划分专用路径，从而实现切片隔离与优先级调度。当在现场可编程门阵列（FPGA）上实现时，该代理每2个时钟周期处理一个数据包，每个时隙最多支持3822个切片。实验结果验证了该方法的可行性、可扩展性及高性能能力，适用于5G后与6G开放RAN部署中的实时、感知切片的上行链路处理。