Short answer: Usually yes, you use them in pairs, but the “pair” can be a media converter on one end and a fiber switch (or SFP in a switch) on the other, as long as both sides speak the same speed, wavelength, and optical mode. 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. In real networks such as campuses, factories, metro POPs converters let you reuse existing switches and still run fiber for long distance, EMI immunity. Sometimes a fiber optic connection is done with dedicated hardware like LAN switches that connect to PCs over UTP and the LAN backbone over dedicated fiber ports. Some video cameras now come with dedicated fiber. Fiber Optic Converters (also known as Media Converters) are devices that convert the electrical signal used in copper wiring such as Ethernet or Serial Data into light waves for transmission over fiber optic cable. Media converters for Ethernet networks can support integrated switch technology, and provide the ability to perform 10/100 and 10/100/1000. FO media converters for Ethernet and fieldbus enable you to convert your copper interfaces to interference-free fiber optics without the need for complex surge protection, shielding, and equipotential bonding measures. Gigabit fiber optic converter with SFP port for 1000Base-T, DIN rail mountable.