GLRE is an OEO based GPON reach extender. It is a physical layer reach extension device in the fiber link between the optical line termination (OLT) and optical network termination (ONT). This active Reach Extender can expand the maximum reach of the fiber link up to 60km as specified in ITU-T GPON standard and also increase overall splitting ratio of the PON. Downstream transmission has 3R regeneration with clock recovery and upstream has 2R regeneration without clock recovery. The reach extender is powered by 100-240V AC source via an AC/DC adaptor. To minimize the power consumption, transmitters in both directions are automatically shut-down when no optical signal from OLT to the reach extender is present.