Yes, it can work with Salt's usual modem if you use the appropriate SFP module for the fiber connection. This converter changes the fiber signal (1000BASE-SX/LX) to Ethernet (10/100/1000Base-T), allowing you to run Ethernet for a few meters and then connect to Salt's router. You need to insert a compatible SFP module into the converter's SFP slot to match the fiber type from Salt's fiber service. The Ethernet port then connects to your router. Note that TP-Link does not guarantee compatibility with all third-party SFP modules, so ensure the SFP module matches Salt's fiber specifications.