TL-FC111A-20 is a 100M media converter, providing a 100M RJ-45 port and a 100M SC fiber port, which can convert between electrical and optical signals. And long-distance data transmission through optical fiber can be applied to commercial scenarios such as park security monitoring and wireless. TL-FC111PB-20 adopts WDM (wavelength division multiplexing) technology, helping send and receive data at a distance up to 20 km with only one single-mode fiber, which saves half of the cable deployment cost for customers compares to dual-fiber deployment.