Selection Points for Single-Fiber Bi-Directional and Dual-Fiber Bi-Directional Links

Single-fiber bi-directional or dual-fiber bi-directional: WDM link selection points

Published: 2025-06-08 EB-LINK Views: 1763 Single fiber bidirectional, dual fiber, WDM, fiber optic transceiver selection

For the same backhaul link, whether a dual-fiber transceiver or a single-fiber bidirectional device is used, the difference lies not in price but in fiber core resources. When there is only one core of optical cable left and it is necessary to transmit and receive at the same time, single fiber is often a more realistic choice; conversely, having a rich fiber core but forcing a single fiber will increase the pairing burden for maintenance.

Dual fiber bidirectional is the most worry-free, but you need to use two cores

One transmits and one receives, the wavelengths at both ends are the same, and the directions are physically isolated by optical fibers, so there is no problem of reverse installation. LC duplex jumper plusGigabit single mode dual fiber one optical one electrical fiber optic transceiverIt is the most common combination, and it is also convenient to use an optical power meter to measure on one side during debugging. The price is one core in each direction, and the backbone core consumption is doubled.

A single fiber separates two directions by wavelength

Using WDM structure, one end sends 1310 and receives 1550, and the other end is just the opposite.
End A and end B must be installed in pairs, and the reverse link will be completely blocked if installed in the opposite direction.
One fiber core can be used in both directions, and point backhaul and fiber core rental scenarios have the greatest benefits.
When running long-distance single-sided operations, pay attention to the dispersion and attenuation differences on the 1550 side.

Like Gigabit single mode single fiber one optical one electrical fiber optic transceiverThis type of paired product is often used when expanding the capacity of monitoring points. There are also corresponding single-fiber models in the 100M range. A two-core optical cable can carry two sets of links.

In these three cases, it is recommended to retain the dual fiber

The first is the long-distance high-speed link of tens of kilometers. The power budget is inherently tight, and the dual-fiber direction isolation is cleaner; the second is the centralized side of the computer room, where dozens of links converge to14-slot box transceiver rackAt this time, paired wavelength management is prone to errors; the third is the campus backbone where the future rate upgrade direction is uncertain, and dual fiber leaves room for replacement of modules with higher nominal distances. Before selecting, please inventory the optical cable coils and available fiber cores, and then decide on single fiber or dual fiber. If you are not sure about the configuration, you can contact EB-LINK to make a list according to the link length and speed, call 0755-83179002.