SM321B
1000Base-BX WDM Bi-Directional SFP Module
Highlights
- WDM Bi-Directional SFP Module
- Supports WDM Bi-Directional technology, using a single strand of fiber, cost saving
Overview
SM321B adopts the latest standard 1000Base-BX, transmitting over a single strand of fiber with one different wavelength going in each direction. It extends network distance up to 20Km with TP-Link's routers, switches, and media converters to provide high speed and stability.
Product Image
A compact, metallic SFP (Small Form-Factor Pluggable) module with a silver casing. It features a green circuit board visible through a clear protective cover on one end, and a standard connector interface on the other. The module has regulatory markings and branding, including "Omada by TP-Link" and "SM321B".
Specifications
Hardware Features & Performance
| Attribute | Value |
|---|---|
| Model | SM321B |
| Standards and Protocols | IEEE 802.3z, TCP/IP |
| Wave Length | TX: 1310 nm RX: 1550 nm |
| Dimensions (W*D*H) | 2.2*0.5*0.5 in (55.4*13.7*12.9 mm) |
| Power Supply | 3.3V |
| Safety & Emission | FCC, CE |
| Cable | Single-mode fiber |
| Fiber Type | 9/125 µm single-mode |
| Max. Cable Length | 20 km |
| Data Rate | 1.25Gbps |
| Port Type | LC Simplex |
| Hardware Features | DDM SFP-MSA Hot Swappable |
| Max. Laser Output Power | 0.501 mW (-3 dBm) |
Physical & Environment
| Attribute | Value |
|---|---|
| Operating Temperature | 0°C to 70°C (32°F to 158°F) |
| Storage Temperature | -40°C to 85°C (-40°F to 185°F) |
| Operating Humidity | 10% to 90% RH non-condensing |
| Storage Humidity | 5% to 90% RH non-condensing |
Some models featured in this guide may be unavailable in your country or region. Visit the Omada by TP-Link website for local sales information: https://www.omadanetworks.com. Specifications are subject to change without notice. ©2025 TP-Link
Related Documents
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TP-Link Omada SM321A-2 1000Base-BX WDM Bi-Directional SFP Module Datasheet Datasheet for the TP-Link Omada SM321A-2, a 1000Base-BX WDM Bi-Directional SFP Module supporting up to 2 km transmission on single-mode fiber with DDM and Hot Swap capabilities. |
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TP-Link Omada SM5110LSB-10 SFP+ LC Module Datasheet Datasheet for the TP-Link Omada SM5110LSB-10, a 10GBase-BX WDM Bi-Directional SFP+ LC Module supporting single-mode fiber, hot-plugging, and DDM. |
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TP-Link SM321A 1000Base-BX WDM Bi-Directional SFP Module Datasheet Datasheet for the TP-Link SM321A, a 1000Base-BX WDM Bi-Directional SFP module supporting up to 20Km over a single strand of fiber. Features LC Simplex, DDM, and hot-swappable capabilities. |
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TP-Link 1000Base-BX WDM Bi-Directional SFP Module Installation Guide Comprehensive installation guide for TP-Link 1000Base-BX WDM Bi-Directional SFP Modules (TL-SM321A, TL-SM321B, TL-SM321A-2, TL-SM321B-2). Includes instructions for installation and removal, detailed specifications, connection diagrams, and regulatory compliance information. |
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TP-Link 1000Base-BX WDM Bi-Directional SFP Module Installation Guide This guide provides instructions for installing and removing TP-Link's 1000Base-BX WDM Bi-Directional SFP Modules (TL-SM321A, TL-SM321B, TL-SM321A-2, TL-SM321B-2). It includes specifications, compatibility information, and safety guidelines. |
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TP-Link Omada SM5110LSA-10 SFP+ LC Module Datasheet Datasheet for the TP-Link Omada SM5110LSA-10 SFP+ LC Module, providing detailed specifications for 10GBase-BX WDM Bi-Directional SFP+ LC connectivity, including hardware features, general specifications, and environmental compliance. |
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Omada SM311LS GBIC Module Datasheet - 1000Base-LX SMF Mini GBIC Technical datasheet for the Omada SM311LS GBIC Module, featuring 1000Base-LX SMF connectivity, up to 20 km transmission, DDM, and SFP-MSA compatibility. |
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TP-Link Omada SFP Module Installation Guide Concise installation guide for TP-Link Omada SFP modules, covering installation, removal, connection, safety information, and declaration of conformity. |