An enhancement to ANSI Technology - Fibre Channel- Physical and Signalling Interface (FC-PH), ANSIX3.240-1994, ANSI Technology - Fibre Channel - Physical and Signalling Interface -2 (FC-PH-2), ANSI X3.297-1997, and ANSI Technology - Fibre Channel - Physical and Signalling Interface-3 (FC-PH-3), ANSI X3.303-1998, are described in 100-SM-LC-L and is an addendum to the FC-PH, FC-PH-2, and FC-PH-3 documents. An extension to the above standards this document describes a low cost, 10 km optical interface.