TP-Link´s TL-SM321A adopts the latest standard 1000Base-BX, transmitting over a single strand of fiber with one different wavelength going in each direction. You can extend the network distance up to 20Km with TP-Link´s routers, switches and media converters to provide high speed and stability.
WDM Bi-Directional SFP Module
Supports WDM Bi-Directional technology, using a single strand of fiber, cost saving