Compare speeds, form factors, compatibility, and choose the right module for ISP networks. SFP modules come in more variations than most people realize. In modern Ethernet networks, choosing the wrong transceiver can result in link failures, speed mismatches, compatibility errors, or unexpected distance limitations. For network engineers, system integrators, and IT. 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. Choosing the wrong one. Selecting the right SFP optical module can be daunting.