FPGA-based 100G network readout solution for SHINE pixel detector

Abstract

With the growing demand for X-ray imaging experiments, the area and performance of pixel array detectors continue to improve, and the readout of massive data gradually becomes a thorny problem. In Shanghai HIgh repetition rate XFEL aNd Extreme light facility (SHINE), the data rate of its high frame rate pixel detector is expected to exceed Tbps in the future. Traditional gigabit and ten-gigabit networks can no longer meet the readout requirements and the transmission bandwidth of the readout system has turned into a bottleneck. Combined with the state-of-the-art developments in the network, two FPGA-based 100G readout solutions are developed. The first solution, NET-CONV, can extract the raw data from the network packet and aggregate data streams from multiple 10G links into one 100G link. It supports parallel transmission of up to 12 channels and achieves a peak rate of 94 Gbps in the test. NET-TOE is developed as the second solution, which aims to improve the transmission speed of the Ethernet ports further. It implements a complete network protocol stack at 100 Gbps line rate, supporting maximum transmission unit (MTU) adjustment, TCP window scale, and UDP. The actual measurement indicates that the maximum data transmission rate reaches 97 Gbps.