SR8: “SR” refers to 100m reach using multi-mode fiber, and “8” implies there are 8 optical channels. Each of the 8 optical channels from an SR8 module are carried on separate fibers, resulting in a total of 16 fibers (8 Tx and 8 Rx). Each optical channel operates at 50Gb/s. The SR8 module uses an MPO-16 connector to connect to 8 fiber pairs. DR4: “DR” refers to 500m reach using single-mode fiber, and “4” implies there are 4 optical channels. Each of the 4 optical channels from a DR4 module are carried on separate fibers, resulting in a total of 8 fibers (4 Tx and 4 Rx). Each optical channel operates at 100Gb/s. The DR4 module uses an MPO-12 connector to connect to 4 fiber pairs. XDR4: “XDR” refers to 2km reach using single-mode fiber, and “4” implies there are 4 optical channels. Each of the 4 optical channels from a DR4 module are carried on separate fibers, resulting in a total of 8 fibers (4 Tx and 4 Rx). Each optical channel operates at 100Gb/s. The DR4 module uses an MPO