Your Programmable NIC Should Be a Programmable Switch

Today's NICs are becoming programmable ("smart"). To support new network protocols, services, and offloads, there are NICs today that have on-board FPGAs, embedded processors, programmable forwarding pipelines, and specialized engines to support features like RDMA. Unfortunately, existing programmable NICs have a number of key limitations. It is difficult to chain offloads, schedule competing accesses to shared resources, and support functions that require variable processing time and thus may not run at line-rate. In this paper, we propose PANIC, a new architecture for programmable NICs that overcomes the limitations of existing NIC designs. We divide the NIC into three components: 1) self-contained offload engines, 2) a logical switch, and 3) a logical scheduler. This design overcomes the limitations of existing designs and is able to scale with increasing line-rates to a large number of offloads and long offload chains.