Two-way gigabit over a single strand of fibre, 20 km out. That's the whole job, and it does it without you pulling a second cable through the conduit.
The SM321A is a WDM bi-directional SFP that sends and receives on one 9/125 μm single-mode fibre pair. You pair it with an SM321B at the far end, plug both in, and traffic flows both directions on the same strand. DDM means you can pull live TX/RX power readings from your switch management interface instead of guessing whether the link is degrading.
Hot-swappable, SFP-MSA compliant, no driver installs. You grab it, drop it in, done. Add to cart and it's heading your way
| brand | TP-LINK |
| model | SM321A |
| type | 1000Base-BX WDM Bi-Directional SFP Module |
| max_transmission_distance | 20 km |
| fibre_type | 9/125 μm Single-Mode Fiber |
| standard | SFP-MSA compliant |
| ddm_support | 1 |
| hot_swappable | 1 |
| pairing_module | TL-SM321B |
| category | TECHNOLOGY > NETWORKING |
