 Layers (AAL). Accelerator Abstraction Layers allow the definition of hardware accelerated components (e.g., fronthaul, timing, GPRS Tunneling Protocol (GTP)/transport, high-PHY) with a com- mon software interface to the (virtualized) host software. Open Radio Access Network (O-RAN) Systems Architecture and Design Examples of other deliverables from this working group cloud deployment scenarios include use-case descriptions and specifications for key requirements, from hardware setups to Linux Kernel PREEMPT_RT latency metrics and container management requirements. Working Group 7: White Box Hardware Workgroup WG7 focuses on the architecture of DU and RU reference hardware design development. Contributing companies are mainly device vendors, such as ADI, Intel, NXP, Qualcomm, Xilinx, and others. Various contributions show how DU and RU equipment can physically be put together using (mainly) these companies' components. The aim is to reduce the effort of hardware architecture and design by standardizing pieces of the solution, thus enabling quicker time-to-market. This working group is operator-led (AT&T, CMCC). Working Group 8: Stack Reference Design Workgroup Just like WG7 architects reference hardware, WG8 focuses on architecture of reference software. Working Group 9: Open X-haul Transport Workgroup WG9 defines an architecture for fronthaul (DU RU), mid-haul (CU<DU), and back- haul (CU core) transport networks. It defines the following: Transport requirements documents. Packet transport network architecture, including timing/synchronization architecture, QoS/queueing models, and target protocol stacks. These documents also include nonideal network architectures, such as DOCSIS (cable modem) and microwave backhaul. Packet transport is defined for both Multi-Protocol Label Switching and Segment Routing over IPv6 dataplane (SRv6) network architectures. Open Radio Access Networks members As we said earlier, O-RAN is an operator-driven standards body to make sure that operator goals such as openness and software ce