Most modern fiber-enabled network switches require an SFP transceiver module featuring a duplex (two strand) multimode OM3 or duplex single mode OS2 connection with LC connectors. Direct attach cables with pre-terminated SFP connections may also be used. Download the Application PDFThis document describes how to troubleshoot fiber optic interfaces by addressing some of the fiber optic module and cabling specifications. There are no specific requirements for this document. This includes Doppler. Fiber optic cabling is increasingly used to connect network switches and other datacom equipment, especially in long-distance and mission-critical applications. Fiber provides: Increased internet signal bandwidth.