ATOP’s APSP31B33xDL40 Small Form Factor Pluggable (SFP+) transceivers are compatible with SFF-8431,SFF-8432 and support 10G Ethernet LR and 10G Fibre Channel .It is designed for use in 10G-Gigabit multi-rate links up to 40km of G.652. Digital diagnostics functions are available via a 2-wire serial interface, as specified in SFF-8472.