D-Link DEM-330T/DEM-330R 1.25G BIDI SFP Module - 10-20KM Compatible

In this review the Jeirdus-compatible SFP BIDI transceiver is presented for network engineers and small data center operators who need a simple, cost-effective way to extend Gigabit links over single-fiber runs. The bottom line: this module delivers the core capability expected from a replacement 1.25Gb/s bidirectional SFP - single LC simplex operation with TX/RX wavelengths of 1310/1550nm and a reach up to 20km - and it is useful where vendor compatibility and tested reliability matter. Our review found it straightforward to deploy and clearly aimed at users replacing D-Link DEM-330T/DEM-330R parts or upgrading mixed-brand networks.

Key Features

• Compatibility: Built to be compatible with D-LINK DEM-330T and DEM-330R modules, making it a direct replacement for existing infrastructure.
• Bidirectional Single-Fiber: Uses 1000BASE-BX-U and 1000BASE-BX-D bidirectional SFP optics to carry transmit and receive on a single LC simplex strand, simplifying fiber runs.
• Range: Rated for operation up to 10-20km over single-mode fiber, suitable for campus links and remote closet connections.
• Interoperability: Jeirdus reports compatibility with Cisco and other brands through a compatibility lab that meets coding requirements for multiple switch and router vendors.
• Quality and Warranty: Each transceiver is individually tested before delivery and is supplied with CE and FCC compliance plus a three year replacement and lifetime warranty.
• Optical Details: Operates at 1.25Gb/s with wavelength pairs TX1310nm/RX1550nm or TX1550nm/RX1310nm for upstream and downstream configurations.

Who It's For

The module suits network administrators who need a drop-in replacement for D-Link DEM-330T or DEM-330R SFPs, or integrators working with mixed-brand environments that include Cisco equipment. It is a practical option for campus backbone links, building-to-building fiber runs, and point-to-point connections where single-fiber simplicity and a 10-20km reach are required.

It is less appropriate for users who need multi-rate fiber optics beyond 1.25Gb/s, multimode fiber environments, or specialized features such as DWDM channelized systems. Organizations requiring vendor-certified optics from the original manufacturer should evaluate their policy before switching to third-party modules.

Pros & Cons

Pros

• Direct compatibility with D-LINK DEM-330T/DEM-330R makes swap-outs simple and predictable.
• Single LC bidirectional design reduces fiber cabling complexity for long runs up to 20km.
• Each unit is individually tested and backed by CE, FCC compliance and a three year replacement plus lifetime warranty.

Cons

• Limited to 1.25Gb/s operation, so it will not future-proof links that will move to 10Gb/s or higher.

Specifications

Our Verdict

The Jeirdus-compatible DEM-330T/DEM-330R BIDI SFP is a solid, cost-effective replacement for networks that require single-fiber Gigabit links and vendor interoperability. It is good value for administrators who need reliable, tested replacement optics with a clear warranty, but it is not intended as a future-proof upgrade path beyond 1.25Gb/s.

Frequently Asked Questions

Will this module work in Cisco switches?
Yes. Jeirdus states the module is compatible with Cisco and other brands after compatibility lab testing to meet coding requirements.

What fiber connector does it use?
It uses a single LC simplex connector for bidirectional single-fiber operation.

How far can the transceiver reach?
It is rated to operate up to 10-20km over single-mode fiber depending on link conditions.