In optical fiber communications, single-mode fiber (SMF) is a type of fiber that transmits light signals directly in a transverse mode. The two primary contenders are Single-Mode Fiber (SMF) optical modules and Multi-Mode Fiber (MMF) optical modules. But which one is right for your project? This guide will demystify the SMF vs MMF debate, helping you make an informed, powerful choice for your infrastructure. Each module type uses LC interfaces, and professionals commonly group them together under the name LC SFP modules. They mainly differ in the type of optical fiber they operate. The 2-channel 1000BASE-BX-D SFP module, also known as Compact SFP, integrates two IEEE 802.