1G optical modules are designed to operate at a data transfer rate of 1 Gigabit per second (Gbps). Working Principle of Optical Module As an essential component of optical fiber communication, optical modules are optoelectronic devices that facilitate the conversion between optical and electrical signals during the transmission process. Most modern networking devices, such as Ethernet switches, servers, routers, network interface cards, and fiber media converters, generally have two or more built-in SFP ports.