Common optical port types for switches include 155M, 1. 25G, 10G, 25G, 40G, and 100G. Switches come in three types: those with only electrical ports, those with only optical ports, and those with a mix of both electrical and optical ports. The following information outlines the differences between switch optical ports and. Optical switches are photonic devices that control the flow of light. At their simplest, they operate as on/off gates, allowing light to pass with low insertion loss in the open state and blocking transmission (causing high insertion loss) when closed.