TP-LINK TL-SM321A-2 1000Base-BX WDM Bi-Directional SFP Module (1550nm TX / 1310nm RX)
SKU: SM321A-2-VER2Networking › Network Accessories
฿385
Price includes 7% VATPrice updated November 2, 2026
In stock19 unitsManufacturer's warranty
For orders placed before 12:00 on a business day; weekends excluded
GenuineFree delivery from ฿5,000Tax invoice
Dual-fiber WDM SFP module for single-fiber Gigabit connectivity up to 20 km. Supports Gigabit connectivity on TP-Link and other network devices supporting SFP-MSA.
Key features
- Supports up to 20 km transmission over a single fiber optic cable.
- Uses dual-fiber WDM technology to save fiber cables.
- Supports DDM for real-time module status monitoring.
- Supports hot-swappable module replacement.
- Works immediately with TL-SM321B-2.
Product description
TP-Link's TL-SM321A-2 module is designed to work with the TL-SM321B-2 module to create a Gigabit network connection over a single fiber optic cable, with a maximum distance of up to 20 kilometers, using WDM (Wavelength Division Multiplexing) technology that transmits data in opposite directions through different wavelengths (TX: 1550 nm, RX: 1310 nm) on a Single-Mode fiber optic cable with a size of 9/125 μm, reducing installation costs and improving performance in long-distance network systems such as branch office connections, data centers, or remote CCTV systems. The module supports real-time operational status monitoring via the DDM (Digital Diagnostic Monitoring) feature, hot-swappable module replacement, and the SFP-MSA standard, enabling immediate compatibility with any switch or network device supporting SFP.
More features
- Supports SFP-MSA standard for compatibility with multiple device models.
- Designed for industrial network environments.
- Operates in temperatures from 0–70 °C.
- Uses 3.3 V power for energy efficiency.
- Compact size and lightweight for easy installation.
Pros and limitations
Pros
- Supports long-distance data transmission up to 20 kilometers using a single fiber optic cable.
- Reduces installation costs by using WDM over a single cable.
- Supports real-time module status monitoring via DDM.
- Compatible with various SFP-MSA-compliant devices.
- Designed to withstand operating temperatures up to 70 °C, ensuring reliable performance in real-world conditions.
Limitations
- Must be used with the TL-SM321B-2 module only to function.
- Does not support connections shorter than 2 kilometers without a paired module.
- Must use only Single-Mode fiber optic cable
Who it is for
Ideal for users who need to extend long-distance networks between offices, data centers, or CCTV systems using a single fiber optic cable to reduce installation costs and improve stability.
Connectivity
LC Connector
Specifications (25)
- Standard
- IEEE 802.3z, TCP/IP
- Data Rate
- 1.25 Gbps
- Interface
- LC Simplex
- Port Type
- LC Simplex
- Cable Type
- Single-Mode Fiber
- Dimensions
- 2.2 x 0.6 x 0.5 in (55.4 x 14.6 x 12.9 mm)
- Fiber Type
- 9/125 μm Single-Mode
- Application
- Gigabit Fiber Communication, Network Extension, CCTV, Data Center Link
- DDM Support
- Yes
- Duplex Mode
- Full-Duplex
- Form Factor
- SFP
- Wave Length
- TX: 1550 nm, RX: 1310 nm
- Power Supply
- 3.3 V
- Compatibility
- Works with TL-SM321B-2 as a pair
- Hot Swappable
- Yes
- Max Cable Length
- 20 KM
- Storage Humidity
- 5–90% RH, Non-Condensing
- Safety & Emission
- FCC, CE
- Transmission Type
- Bi-Directional WDM
- Operating Humidity
- 10–90% RH, Non-Condensing
- Storage Temperature
- -40–85 °C (-40–185 °F)
- Operating Temperature
- 0–70 °C (32–158 °F)
- SFP-MSA Compatibility
- Yes
- Wavelength Separation
- 1550 nm / 1310 nm
- Digital Diagnostic Monitoring
- Yes (SFF-8472 compatible)
Datasheets and manuals straight from the manufacturer — select a document to open or download it.
13 questions
Frequently asked questions about this product
Compiled from manufacturer information
What switch models is the TL-SM321A-2 module compatible with?
This module supports devices that comply with the SFP-MSA standard, particularly TP-Link switches with SFP ports such as Omada Series, TL-SG3424, TL-SG3410, etc. It can be used immediately if an SFP port is available.
Can this module be used with a single fiber optic cable?
Yes, the TL-SM321A-2 module is designed to work with the TL-SM321B-2 module over a single fiber optic cable, transmitting data in opposite directions using different wavelengths (1550 nm and 1310 nm), significantly reducing fiber usage.
What is the maximum distance supported by this module?
This module supports a maximum transmission distance of up to 20 kilometers over a Single-Mode fiber optic cable with a size of 9/125 μm, making it ideal for connecting branch offices or data centers located far apart.
Does this module have a feature to monitor its condition?
Yes, this module supports the DDM (Digital Diagnostic Monitoring) feature, allowing real-time monitoring of operational status such as temperature, voltage, transmit/receive optical power through the network or management software.
Must a matching module be used for it to work?
Yes, this module must be used in conjunction with the TL-SM321B-2 module, which has the opposite wavelength (TX: 1310 nm, RX: 1550 nm), to enable Full-Duplex communication over a single fiber, ensuring complete functionality.
How much power does this module use?
This module uses 3.3 V power, which is standard for most SFP modules, requiring no additional equipment. It supports hot-swappable operation without shutting down the device.
Can it be used in industrial environments?
Yes, this module supports an operating temperature of 0–70 °C and humidity of 10–90% RH non-condensing, making it suitable for use in offices, data centers, or harsh environments.
Is there a warranty?
No warranty information is available from the provided sources, but this module is a TP-Link business-grade product, so it is highly reliable. Contact the sales team immediately for additional warranty details.
Is it in stock?
The TP-LINK TL-SM321A-2 1000Base-BX WDM Bi-Directional SFP Module (1550nm TX / 1310nm RX) is in stock and ready to ship. Orders placed before 12:00 on a business day are delivered within 1–3 business days (Bangkok and vicinity) or 2–5 business days (other provinces). Order online at store.gist.co.th or contact our sales team at 092-251-4017.
How much does it cost?
The price is ฿385 (including 7% VAT). It is in stock and ready to ship. Business customers can request a quotation at sales@gist.co.th.
How long is the warranty?
The warranty follows the manufacturer's terms for each model; ask our sales team for the warranty period of this model. To make a warranty claim, call 092-251-4017 or 065-523-5262, or email sales@gist.co.th (Mon–Fri 9:00–18:00), then send the product with your order number to our head office, or bring it to the head office in person.
How long does delivery take?
Orders placed before 12:00 on a business day are delivered within 1–3 business days (Bangkok and vicinity) or 2–5 business days (other provinces). Free delivery on orders of ฿5,000 or more (a ฿150 delivery fee applies below this amount).
Is it genuine?
Genuine products sourced from distributors in Thailand, covered by the manufacturer's warranty. Full tax invoices are available.
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Genuine products
Sourced from distributors in Thailand and covered by the manufacturer's warranty
Warranty period
According to the manufacturer's terms for each model
Covered by the manufacturer's warranty; you can make claims through GIST
Claims through GIST
Ship the product to our head office or bring it in person
Warranty conditions
- A receipt or other proof of purchase is required
- The product must not have been modified or altered
- Damage caused by misuse is not covered by the warranty
- To make a warranty claim, call 092-251-4017 or 065-523-5262, or email sales@gist.co.th (Mon–Fri 9:00–18:00), then send the product with your order number to our head office, or bring it to the head office in person.Head office: 554 Sky Nine Center, Floor 12A, Room 554/62, Asok-Din Daeng Road, Din Daeng Subdistrict, Din Daeng District, Bangkok 10400
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Price
฿385