1000BASELX

1000BASE-LX is an Ethernet physical-layer standard for transmitting 1 gigabit per second over optical fiber. It is defined as part of the IEEE 802.3 family and uses a long-wavelength laser (LX) at 1310 nanometers to carry the data. The designation LX indicates the intended long-distance operation over fiber.

The standard is designed for fiber-optic links, with single-mode fiber as the primary medium. It is commonly implemented through fiber transceivers that plug into network equipment via standard SFP or GBIC modules. The optical link operates in full-duplex mode and is typically used for point-to-point connections between devices such as switches and routers.

Distance specifications for 1000BASE-LX are tied to the use of single-mode fiber. As defined in the original standard, links on SMF are typically up to about 5 kilometers, depending on fiber characteristics and optical components. Longer distances are associated with other technologies in the 1000BASE family, such as 1000BASE-ZX, which are designed for longer reach.

Connectors and interfaces are device- and vendor-dependent, but LC duplex connectors are common in modern 1000BASE-LX implementations. Transceivers may be integrated into switches or deployed as modular SFP/GBIC devices, enabling flexible interconnection over existing fiber infrastructure.

In deployment, 1000BASE-LX is used for campus networks, data-center interconnects, and building-to-building links where single-mode fiber is available and distances fall within the standard’s reach. Related standards include 1000BASE-SX for short-range MMF and 1000BASE-ZX for extended-distance applications.