 team and compared against performance targets as set during the system architecture phase. Consider aspects such as: I/O termination: Performance is counted in Gbps or number of carriers/antennas and the associated clock cycle count/Central Processing Unit (CPU) loading associated with this throughput indication. Worst case scenarios are defined up-front for fronthaul, based on compression, fragmentation, beamforming, etc. These numbers should include validation against latency requirements as outlined for the DU and RU. Latency can be measured by using General Purpose Input/Output (GPIO) toggles triggering an oscilloscope or other hardware measurement tool or by timestamping in a CPU core for a software-centric implementation. Signal processing chain: Signal processing performance is measured both in terms of (1) algorithmic performance as compared to an MATLAB reference using waterfall charts and similar tools and (2) cycle count performance against the targets as defined during systems architecture phase. Stack/packet processing: Performance is measured using cycle counting (as for signal processing performance), throughput benchmarking as for I/O termination performance, or a combination of the two. Stack performance testing is highly dependent on the parameters 332 Open Radio Access Network (O-RAN) Systems Architecture and Design with which the device under test (DUT) is configured, including packet size (64 byte, IMIX/ 390 byte or large packet/1024 byte); stack featured (PDCP encryption mode, RLC retransmission mode); and system configuration (number of connected/active/scheduled users, etc.). Partitioning of the system over CPU cores can mean that secondary performance bottlenecks become visible only after primary bottlenecks have been found, putting more emphasis on early benchmarking, during the development cycle. System test setup System tests include multiple components such as the combination of a Physical Layer and a MAC/RLC/RRC stack in the case of a DU system and thus include the interface between