Alistar 1G 1000BASE-LX Optical SFP Module, 2SM, LC Duplex, 20 km, 1310 nm, DDM

The Alistar 1G 1000BASE-LX optical SFP module is designed for data transmission at speeds of up to 1 Gbps over two single-mode optical fibers. The transceiver operates at a wavelength of 1310 nm and supports optical links over distances of up to 20 km.

The module is equipped with an LC Duplex optical interface: one fiber is used for signal transmission and the second for signal reception. This solution is suitable for connecting network switches, routers, media converters, and other equipment fitted with a compatible Gigabit SFP port.

Support for DDM (Digital Diagnostic Monitoring) enables monitoring of the transceiver’s key operating parameters through the interface of compatible network equipment. This simplifies optical link diagnostics and helps detect signal degradation or other connection issues in time.

Main advantages

• Data rate up to 1 Gbps — suitable for building high-performance Gigabit Ethernet networks.
• Transmission distance up to 20 km — ideal for links between remote buildings and network nodes.
• Single-mode fiber support — operates over two SM optical fibers.
• LC Duplex connector — compact dual-fiber optical interface.
• 1310 nm wavelength — a standard solution for transmission over single-mode fiber.
• DDM support — digital monitoring of the transceiver and optical link status.
• Versatile application — suitable for switches, routers, and media converters with a compatible SFP port.

How the module works

The optical transceiver converts the electrical signal from network equipment into an optical signal and transmits it over single-mode fiber. At the opposite end of the link, a second compatible SFP module receives the optical signal and converts it back into an electrical signal.

Two separate optical fibers are used for data transmission and reception:

• one fiber for transmitting data;
• one fiber for receiving data.

To establish a connection, compatible SFP modules with matching data rates, fiber types, and operating wavelengths must be installed at both ends of the optical link.

DDM function

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

Depending on the capabilities of the switch, router, or media converter, the following parameters can be monitored:

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

DDM helps assess the quality of the optical connection, check the available signal margin, and identify potential line faults more quickly.

Applications

• connections between network switches;
• links between remote buildings and offices;
• corporate and local area networks;
• server rooms and data centers;
• telecommunications nodes;
• IP video surveillance systems;
• Gigabit media converter connections;
• optical links with distances of up to 20 km.

Technical specifications

What is required for connection

• two compatible Gigabit 1000BASE-LX SFP modules;
• a dual-fiber single-mode optical link;
• a fiber-optic patch cord with LC Duplex connectors;
• a switch, router, or media converter with a compatible SFP port.

Installation recommendations

1. Make sure the network equipment supports Gigabit SFP modules.
2. Install the transceiver into the SFP port of the network device.
3. Connect a single-mode LC Duplex fiber-optic patch cord.
4. Install a compatible module at the opposite end of the link.
5. Check that the transmit and receive channels are connected correctly.
6. After the link is established, check the LINK indicator and available DDM parameters.

Frequently asked questions

Which optical cable is suitable for this SFP module?

A single-mode optical fiber and a fiber-optic patch cord with LC Duplex connectors are required.

How many fibers are required?

Two optical fibers are used: one for signal transmission and one for signal reception.

Which module should be installed at the opposite end?

A compatible 1G 1000BASE-LX SFP module for single-mode fiber operating at 1310 nm should be installed at the opposite end.

Can the module be used with a media converter?

Yes, provided that the media converter has a compatible Gigabit SFP port and supports 1000BASE-LX modules.

What is DDM used for?

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

Will the module always provide a 20 km transmission distance?

The actual transmission distance depends on the quality of the optical fiber, the number of connections and splices, connector condition, total link attenuation, and the specifications of the equipment installed at both ends.

The Alistar 1G 1000BASE-LX optical SFP module with an LC Duplex connector, a 1310 nm wavelength, and a transmission distance of up to 20 km is a practical solution for building stable Gigabit links over two single-mode optical fibers. DDM support simplifies transceiver monitoring, optical link diagnostics, and network maintenance.