SFP LX (Small Form-Factor Pluggable Long-Reach) and SFP LH (Small Form-Factor Pluggable Long Haul) are both types of SFP (Small Form-Factor Pluggable) transceivers used in optical communication. While they share some similarities, there are key differences between them:

1. Distance Reach:

• SFP LX: LX typically stands for "Long-Reach" or "Long-Range," and SFP LX modules are designed for relatively shorter distances compared to LH modules. SFP LX modules commonly support distances of up to 10 kilometers (km) over single-mode fiber.

• SFP LH: LH stands for "Long Haul," indicating that SFP LH modules are designed for longer-distance communication. SFP LH modules can support distances greater than 10 km, often in the range of 40 km to 100 km or more over single-mode fiber.

2. Wavelength:

• SFP LX: The SFP LX modules typically operate at a wavelength of around 1310nm.

• SFP LH: SFP LH modules may also operate at a wavelength of 1310nm, but they can sometimes use different wavelength ranges depending on the specific implementation.

3. Applications:

• SFP LX: SFP LX modules are commonly used in metropolitan and enterprise networks where moderate-distance connectivity is required.

• SFP LH: SFP LH modules are suitable for long-distance connections, often used in applications like long-haul telecommunications and network connections between cities.

4. Fiber Type:

• Both SFP LX and SFP LH modules are typically used with single-mode fiber (SMF). Single-mode fiber allows for longer-distance communication by reducing signal dispersion.

It's important to note that terminology and specific characteristics may vary among manufacturers, and sometimes the terms LX and LH might be used interchangeably. Therefore, it's advisable to refer to the specifications provided by the transceiver manufacturer to ensure accurate information for a particular module.