Module for operation over two optical fibers in SFP format for Gigabit Ethernet (1000Base-SX). Designed to work on multimode optical fiber (MMF), maximum range is 550 m (fiber 50/125 µm), optical budget is 8dBm, LC connectors, working wavelength is 850 nm. One is transmitting port, and the other one is receiving port. BIDI module only has 1 port, wave filtering through the filter of module, and finished the transmitting of 1310nm optical signal. Fiber Optic Transceivers are compact devices designed to transmit and receive data over a fiber optic cable. Dual fiber modules use two fibers. They are easier to set up and give steady communication. Cisco offers a range of GBIC, SFP, XFP, SFP+, CXP, CFP, Cisco CPAK, and QSFP+ pluggable modules.