SFP modules are categorized into three main types based on the transmission medium: Optical, Copper, and Direct Attach. 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 serves as a crucial component in optical fiber communication systems, operating at the physical layer, which is the lowest layer in the OSI model. By understanding these tech advancements, companies can get better at leveraging Optical. To meet the demands of various transmission rates, different-rate optical modules have emerged: 1.