Fibre Optic Mode-Conditioning Cable
Use Fibre Optic Mode-Conditioning Cable for Gigabit Ethernet longer than 550 meters
You can run Gigabit Ethernet over up to 2-km-long multimode fibre optic cable. However, the transceiver modules used for long-wave (1310-nm) Gigabit Ethernet (1000BASE-LX) launch only single-mode signals. So if you have multimode fibre cable longer than 550 meters in your existing system, you can use it for Gigabit Ethernet by using Fibre Optic Mode-Conditioning Cables.
Launching a single-mode laser into the centre of a multimode fibre can confuse the receiver at the other end if multiple signals are generated. Differential Mode Delay (DMD) effects create these multiple signals, which severely limit cable distance lengths for operating Gigabit Ethernet. Fibre Optic Mode-Conditioning Cables offset the single-mode laser launch from the centre of a multimode fibre, which eliminates the multiple signals and enables a launch similar to a typical multimode LED launch.