Cisco 1000BASE-SX SFP Transceiver Module, 850 nm Multimode with DOM

Gigabit fiber over multimode cable, with digital optical monitoring, is the role of the Cisco 1000BASE-SX SFP Transceiver Module with DOM, part number GLC-SX-MMD. It operates at 850 nm and uses a duplex LC connector at 1GbE.

DOM lets the host read optical power and related values from the module, which helps when troubleshooting a link. The feature is named in the title, so check your switch documentation for which values the host reports.

Reach depends on the fiber: 550 m on legacy 50 um fiber and 220 m on 62.5 um FDDI-grade fiber. Those figures suit building backbones and older campus cabling built before faster multimode grades became common.

The form factor is SFP. The number GLC-SX-MM is recorded as a superseded part number for this module, so a supplier listing under that older code may be referring to the same family. Confirm the DOM version when you need it.

The GLC-SX-MMD is offered new, refurbished and used. New and refurbished modules carry 1 year or 3 years of warranty, and used modules carry 90 days. Send your quantity and host platform when you request pricing.