# TP-Link TL-SM321B-2 1000Base-BX WDM Bi-Directional SFP Module

- Canonical URL: https://www.netxl.com/fibre-modules-and-cables/tp-link-bi-directional-sfp-module-sm321b-2/
- Brand: TP-Link
- SKU / part number: TL-SM321B-2
- EAN (GTIN-13): 6935364072940
- Category: Fibre Modules & Cables (https://www.netxl.com/fibre-modules-and-cables/)

## Pricing (GBP, guest pricing — trade customers see account pricing via the API)
| Quantity | ex VAT | inc VAT |
| --- | --- | --- |
| 1+ | £16.67 | £20.00 |
| 5+ | £16.60 | £19.92 |
| 10+ | £16.54 | £19.85 |

## Availability and shipping
- Availability: 50 in stock
- Shipping: Royal Mail Tracked - Next Working Day — £7.19, 1 working day(s)

## Description

The TP-Link TL-SM321B-2 is a 1000Base-BX WDM bi-directional SFP module offering fast, reliable gigabit fiber connectivity up to 2 km over 9/125 single-mode fiber. Featuring hot-swappable SFP-MSA compliance and Digital Diagnostic Monitoring (DDM), it is ideal for switches, routers, and servers requiring short to medium distance optical links.

The TP-Link TL-SM321B-2 optical transceiver utilizes WDM bi-directional technology to transmit data up to 2 km over a single strand of 9/125 single-mode fiber using an LC simplex connector interface. Operating at 1310 nm Tx and 1550 nm Rx, it delivers 1.25 Gbps data transfer speeds for enterprise switches, routers, and servers.
Built in accordance with the Small Form-Pluggable Multi-Source Agreement (SFP-MSA), the transceiver is hot-swappable for seamless deployment without network disruption. Integrated Digital Diagnostic Monitoring (DDM) compliant with SFP-8472 enables real-time tracking of critical operational parameters, including optical power levels, transceiver current, and operating temperature.

## Key highlights

- 1000Base-BX WDM bi-directional transceiver
- Up to 2 km transmission distance
- 1.25 Gbps data transmission speed
- Tx 1310 nm / Rx 1550 nm wavelength
- LC Simplex optical connector
- Digital Diagnostic Monitoring (DDM)
- SFP-MSA compliant and hot swappable

## What's in the box

- SFP Module TL-SM321B-2
- Installation Guide

## Specifications

| Specification | Value |
| --- | --- |
| WiFi | 0 |
| Range (m) | Up to 2,000m |
| Throughput Speed | 1000Mbps |
| PoE | 0 |

## Programmatic access

- This page in HTML: append a trailing slash instead of `.md`
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- Machine-readable site index: https://www.netxl.com/llms.txt
- API documentation: https://www.netxl.com/api-docs.md