In a simplex communication system, signals travel in a single direction from the transmitter to the receiver, with no return path. Broadcast radio and television are classic examples of simplex transmission. In networking, a simplex fiber optic cable uses a single strand of glass to push data one way, requiring a second strand if bidirectional communication is needed.
Heard on the job
We're running a simplex fiber link to the remote monitor since it only needs to send telemetry back to base.