Some combinations of physical layers and data transmission
protocols were considered in this study. Small formfactor
pluggable plus (SFP+) and quad small form-factor
pluggable plus (QSFP+) physical layers with optical MGTs
were selected; the optical MGT is required for long-distance
communication with electrical isolation from the sensor. For
transmission protocols, Aurora and the X (ten) attachment unit
interfaces (XAUI) were studied. The Aurora protocol is simple
1620
and easy to implement for high bandwidth communication via
the bonding of lanes. XAUI is a standard extension of the
lO-GbE Media Independent Interface (MIl) and can build a
lO-GbE physical layer with a lower bandwidth MGT (3.125
Gbps x 4 transceivers).