PGP4: A Pretty Good Protocol for 10+ Gigabit FPGA-to-FPGA Communication

Modern High Energy Physics and Photon Science experiments now require high-speed serial data links of 10 Gbps or higher for their data acquisition systems. These links must be lightweight, with low protocol overhead and small FPGA resource utilization. Often these links will multiplex data from several sources, so the link protocol should also support the concept of multiple "Virtual Channels" per physical link. Based on our experience developing the PGP2 protocol, which supported link rates of up to 6 Gbps using 8b/10b encoding, we present will present PGP Version 4 (PGP4) protocol to support link rates in excess of 15 Gbps using 64b/66b encoding.