Augmenting data plane functionality with field programmable integrated circuits

Abstract

Some embodiments provide novel circuits for augmenting the functionality of a data plane circuit of a forwarding element with one or more field programmable circuits and external memory circuits. The external memories in some embodiments serve as deep buffers that receive through one or more FPGAs a set of data messages from the data plane (DP) circuit to store temporarily. In some of these embodiments, one or more of the FPGAs implement schedulers that specify when data messages should be retrieved from the external memories and provided back to the data plane circuit for forwarding through the network. For instance, in some embodiments, a particular FPGA can perform a scheduling operation for a first set of data messages stored in its associated external memory, and can direct another FPGA to perform the scheduling operation for a second set of data messages stored in the particular FPGA's associated external memory. Specifically, in these embodiments, the particular FPGA determines when the first subset of data messages stored in its associated external memory should be forwarded back to the data plane circuit to forward to data messages in the network, while directing another FPGA to determine when a second subset of data messages stored in the particular FPGA's external memory should be forwarded back to the data plane circuit.