Notes:
From Ethernet - The Definitive Guide
1000BaseFx uses 8B/10B ANSI X3T11 Fibre Channel FC-1 frame encoding, serializer/deserializer (SERDES) and NRZ on the fiber, clocked at 1250 Mbaud.
Since LEDs are "only" capable of modulating to 622 MHz, lasers must be used at these bandwidths.
Links of over 100Km have been demostrated.