TP-LINK TL-SM321B 1000Base-BX WDM Bi-Directional SFP Module

The TP-LINK TL-SM321B is a 1000Base-BX WDM bi-directional SFP transceiver module designed for long-distance fiber optic network connectivity. This module enables bidirectional communication over a single fiber strand, transmitting data at 1.25 Gbps across distances up to 20 kilometers using 9/125 μm single-mode fiber.

Key Features

• Up to 20 km transmission distance with 9/125 μm SMF (Single-Mode Fiber)
• Bidirectional WDM communication on a single fiber
• Compatible with Small Form Pluggable Multi-Source Agreement (SFP-MSA)
• Supports Digital Diagnostic Monitoring (DDM)
• Hot-swappable module design
• Work with TL-SM321A as a pair

What This Product Does

TP-Link's TL-SM321B adopts the latest standard 1000Base-BX, transmitting over one single-mode fiber with one different wavelength going in each direction. Paired with TL-SM321A, you can extend the network distance up to 20km with TP-Link's routers, switches and media converters for reliable high-speed long-distance communication.

The module operates using wavelength division multiplexing (WDM) technology, transmitting at 1310 nm while receiving at 1550 nm through an LC simplex connector. This wavelength configuration must be paired with the TL-SM321A module, which uses the opposite wavelength configuration, to establish a complete bidirectional link.

Technical Specifications

The TL-SM321B complies with IEEE 802.3z standards and operates at 3.3V power supply. The module features hot-swappable capability, allowing installation and removal without powering down network equipment. Digital Diagnostic Monitoring (DDM) functionality provides real-time monitoring of module parameters including temperature, voltage, transmit power, and receive power.

Operating temperature range spans 0–70 °C with storage capability from -40–85 °C. The module maintains reliable performance in humidity conditions from 10–90% RH during operation and 5–90% RH during storage, making it suitable for various deployment environments.

Description

Specification

• Device Type: SFP Module
• Standards and Protocols: "IEEE 802.3z, TCP/IP"
• Cable: Single-mode Fiber
• Fiber Type: 9/125 um Single-mode
• Max. Cable Length: 20k m
• Data Rate: 1.25 Gbps
• Wave Length: TX: 1310 nm
  RX: 1550 nm
• Port Type: LC Simplex
• Power Supply: 3.3V
• Environment: "Operating Temperature: 0–70 °C (32–158 °F)
  Storage Temperature: -40–85 °C ( -40–185 °F)
  Operating Humidity: 10–90% RH, Non-Condensing
  Storage Humidity: 5–90% RH, Non-Condensing"
• Package Contents: SFP Module TL-SM321B
  Installation Guide
• Package Type: Retail
• Package Weight: 0.0300 kg
• Warranty: Limited Lifetime