FlexDriver: A Network Driver for Your Accelerator

We propose a new system design for connecting hardware and FPGA accelerators to the network, allowing them to directly control commodity ASIC NICs without using the CPU. This solves the key challenge of leveraging existing NIC hardware offloads such as RDMA and virtualization for hardware disaggregation and accelerator networking. Our approach supports a diverse set of use cases, from direct network access for disaggregated accelerators to inline acceleration of the network stack and disaggregation of main system memory, all without implementing complex networking logic.

To demonstrate this approach, we build FlexDriver (FLD) , a hardware module that implements a NIC data-plane driver. Our main technical contribution is compressing NIC control structures by 5 ×, allowing FLD to achieve high scalability with low die area and no memory bandwidth interference.

We build two prototypes – FLD core on NVIDIA Innova-2 FPGA SmartNICs and FLD with a load/store interface on IBM OpenCAPI FPGA deployment with ConnectX-6 Dx. We demonstrate four different use cases: a disaggregated LTE cipher, an IP-reassembly inline accelerator, an IoT cryptographic-token authentication offload, and a fine-grained memory disaggregation datapath over RDMA. These leverage the ASIC NIC for RDMA processing, VXLAN tunneling, and traffic shaping, without CPU involvement.