Based on the NVIDIA Mellanox ConnectX-4 controller (MT27700 family), the MCX455A-ECAT class VPI adapter delivers 100GbE and EDR InfiniBand via a single QSFP28 port and PCIe 3.0 x16 host interface. It supports SR-IOV and RDMA/RoCEv2 for low-latency virtualization and storage, plus VXLAN/NVGRE offloads for overlay networks. The QSFP28 cage accepts QSFP28 DAC/AOC or 100GBASE-SR4/LR4 optics (not RJ45/SFP+). Brackets: full-height included; low-profile optional for 2U/short-depth chassis. OS/virtualization stacks such as Linux, ESXi, and KVM are widely used with ConnectX-4. Also referred to as a PCI network adapter by users (PCIe interface). For compliance, Ethernet operation aligns with IEEE 802.3ba/bm 100GbE and InfiniBand with IBTA EDR; ensure correct cables/transceivers and adequate chassis airflow for the passive heatsink.