Cisco GLC-LH-SM 1000BASE-LX/LH SFP Transceiver Module – 1310nm, 10km SMF, LC (Used – Grade A)

Reliable Gigabit fiber links up to 10 km for Cisco networks. Tested Grade A used module.

The Cisco GLC-LH-SM is a 1000BASE-LX/LH SFP transceiver that carries 1 Gbps Ethernet over single-mode fiber using a 1310 nm laser and duplex LC connector. It is used to connect switches between floors, buildings and campus sites at distances up to 10 km. This unit is used, tested and in Grade A condition.

Choosing the Right Optic for Reliable Fiber Links

Copper Ethernet is limited to 100 m, which is not enough between buildings or across a large campus. The wrong optic causes link errors, unsupported-transceiver warnings or links that never come up.

The GLC-LH-SM follows the IEEE 1000BASE-LX/LH standard using a 1310 nm laser, so it links reliably with any compliant optic at the other end. Over single-mode fiber it reaches 10 km, and it can also run up to 550 m on multimode fiber with a mode-conditioning patch cord.

As a Cisco optic, it is recognized by Cisco IOS, IOS XE and NX-OS without needing the “service unsupported-transceiver” workaround, and digital optical monitoring reports light levels for troubleshooting.

Long-Reach Single-Mode Performance

LX/LH optics are the standard choice for inter-building and campus backbone links, where single-mode fiber carries a Gigabit signal far beyond multimode limits.

Hot-Swappable with Built-in Diagnostics

The module can be inserted or removed while the switch is running. DOM values such as transmit power, receive power and temperature are available through “show interfaces transceiver”, making it easier to find dirty connectors or damaged fiber. Each used module is tested for link and DOM readings before shipping.

How to Install the Cisco GLC-LH-SM

1. Confirm the host port is an SFP or SFP+ port that supports 1000BASE-LX and that the other end uses a matching optic.
2. Remove the dust plug and insert the transceiver into the port until it clicks into place; the latch should face the correct direction for the port.
3. Clean the fiber connectors, then connect a duplex LC single-mode (OS2) patch cord, crossing transmit and receive.
4. Check the link with “show interfaces status” and verify optical levels with “show interfaces transceiver”.