Alistar 1G 1000BASE-BX BiDi WDM Optical SFP Module, 1SM, SC, 20 km, TX1550/RX1310 nm, DDM

The Alistar 1G 1000BASE-BX BiDi WDM optical SFP module is designed for building Gigabit fiber-optic links with data transmission rates of up to 1 Gbps. The transceiver operates over single-mode optical fiber and provides stable data transmission over distances of up to 20 km.

Thanks to BiDi WDM technology, data transmission and reception are carried over a single optical fiber using different wavelengths. The module transmits at 1550 nm and receives at 1310 nm. To establish a complete optical link, it must be paired with a compatible TX1310/RX1550 nm module.

The transceiver is equipped with an SC Simplex optical connector and supports DDM (Digital Diagnostic Monitoring), which enables monitoring of the module’s key operating parameters through the interface of compatible network equipment.

Main advantages

• Data rate up to 1 Gbps — supports the 1000BASE-BX Gigabit Ethernet standard.
• Single-fiber connection — BiDi WDM technology enables data transmission and reception over one optical fiber.
• Transmission distance up to 20 km — suitable for connecting remote buildings, offices, and network nodes.
• Single-mode fiber support — designed for SM 9/125 µm optical fiber.
• SC Simplex connector — a reliable and widely used optical interface.
• DDM support — digital monitoring of the transceiver’s condition and operating parameters.
• Hot-swappable design — the module can be installed or replaced without shutting down compatible equipment.
• Broad compatibility — suitable for switches, routers, and media converters with a Gigabit SFP slot.

BiDi WDM technology

In a conventional duplex optical link, separate fibers are used for transmitting and receiving data. BiDi WDM technology enables bidirectional communication over a single single-mode fiber by separating the channels by wavelength.

This SFP module operates as follows:

• transmit wavelength TX — 1550 nm;
• receive wavelength RX — 1310 nm.

A paired module with TX1310/RX1550 nm parameters must be installed at the opposite end of the link. Two identical TX1550/RX1310 nm modules will not establish an optical connection.

DDM function

DDM is a digital diagnostic monitoring function that provides information about the current condition of the SFP module through compatible network equipment.

DDM allows the following parameters to be monitored:

• transceiver temperature;
• supply voltage;
• laser bias current;
• transmitted optical power;
• received optical signal level.

Monitoring these parameters helps detect signal degradation, excessive optical loss, or potential equipment faults in time.

Applications

• connecting remote offices and buildings;
• creating Gigabit optical links between switches;
• IP video surveillance systems;
• local and corporate networks;
• server rooms and telecommunications nodes;
• connecting equipment through media converters;
• building backbone and distribution fiber-optic links;
• extending networks over distances of up to 20 km.

Technical specifications

How to choose the paired SFP module

A single-fiber optical link requires two modules with complementary transmit and receive wavelengths. The TX1550/RX1310 nm module must be paired with a TX1310/RX1550 nm transceiver.

Both modules should support:

• 1 Gbps data transmission;
• the 1000BASE-BX BiDi standard;
• transmission distances of up to 20 km;
• single-mode optical fiber;
• an SC Simplex connector;
• single-fiber WDM technology.

Connection recommendations

1. Install the SFP module in a compatible Gigabit SFP slot on a switch, router, or media converter.
2. Connect a single-mode fiber-optic patch cord with an SC connector.
3. Install the paired TX1310/RX1550 nm module at the opposite end of the link.
4. Check that both modules match in data rate, transmission distance, and fiber type.
5. Verify that the optical link indicator is active.
6. If DDM is supported, check the received optical signal level through the equipment interface.

Frequently asked questions

Which module is required at the opposite end of the link?

A paired 1000BASE-BX BiDi SFP module with TX1310/RX1550 nm wavelengths, an SC connector, and a transmission distance of up to 20 km is required.

Can two identical modules be used?

No. A single-fiber BiDi WDM connection requires modules with complementary wavelengths. A TX1550/RX1310 nm module must be paired with a TX1310/RX1550 nm module.

Which optical fiber is required?

One single-mode SM 9/125 µm optical fiber is required.

Which fiber-optic patch cord is required?

A single-mode fiber-optic patch cord with an SC connector and a polishing type compatible with the installed equipment is required.

What is DDM used for?

DDM allows temperature, voltage, laser bias current, transmitted optical power, and received optical signal level to be monitored through compatible network equipment.

Is the module suitable for a media converter?

Yes, provided that the media converter has a Gigabit SFP slot and supports 1000BASE-BX BiDi modules.

The Alistar 1G 1000BASE-BX BiDi WDM optical SFP module with an SC connector and TX1550/RX1310 nm wavelengths is a practical solution for building stable Gigabit fiber-optic links over distances of up to 20 km using a single single-mode fiber. DDM support simplifies network monitoring, diagnostics, and maintenance.