BiDirectional XFP optical transceivers transmit data over a single optical fibre (simplex).
10G CWDM XFP optical modules transmit data in the second and third transmission windows (1270-1610nm).
10G DWDM XFP optical transceivers are available in 100GHz and 50GHz versions. They enable transmission over a range of 1563.86nm to 1528.77nm.
10G Tunable XFP transceivers contain a tunable laser owing to which they can be adjusted to work in any channel of 50-GHz DWDM system in the range of 110 (1568.80nm) to 615 (1528.40nm).