Most systems operate by transmitting in one direction on one fiber and in the reverse direction on another fiber for full duplex operation. Single fiber modules (BiDi) use one fiber for both transmitting and receiving data. A 1-core fiber is like a single-lane road—only one car (or data signal) can travel at a. SFP (Small Form-factor Pluggable) is a compact, hot-pluggable network interface module used to connect network devices (switches, routers, firewalls) to fiber optic or copper cables. Think of it as the “translator” for your network equipment, converting electrical signals into optical signals. The optical module (opTicalmodule) is composed of optoelectronic devices, functional circuits and optical interfaces. An. ts for data communications applications.