The mfefx1 is an easy to install mini gbic sfp transceiver module that provides a simple way to add 100 base fx functionality to your linksys switch the module operates at a wavelength of 1310 nanometer and supports multi mode fiber optic cabling in a typical operating environment it can achieve distances up to 2 km depending on the total attenuation in the fiber plant 100 base fx is mainly used within a building or in small campus networks needing 100 mbps connectivity between sites the