Before You Buy
What do I need to know about upstream and downstream SFPs?
Upstream and downstream SFPs function the same way as other SFPs, except that they use Wavelength-Division Multiplexing (WDM). WDM allows for the transmitting and receiving signals to co-exist on the same fiber strand. This allows a single fiber cable strand to simultaneously transmit and receive a signal.
You must use upstream and downstream SFPs in pairs. You cannot use two upstream or two downstream SFPs together.