Every WhaleyComm unit is professionally tested, reset to factory defaults, and certified by our in-house engineers — the same standard trusted by 5,000+ organisations across 25 years. Not a refurb marketplace. A certified lifecycle partner.
Tested to factory specification. Backed by 25 years of enterprise trust.
The Cisco GLC-SX-MMD is a industry-standard 1000BASE-SX Small Form-factor Pluggable (SFP) transceiver engineered for Gigabit Ethernet and 1G Fibre Channel applications over multimode fiber. Operating at an 850nm wavelength with a duplex LC fiber connector interface, this module is a trusted solution for short-reach intra-building and campus network deployments.
Designed to integrate seamlessly into Cisco Catalyst switches, routers, and other SFP-compatible platforms, the GLC-SX-MMD supports link lengths of up to 550 meters over 50/125µm OM2 multimode fiber and up to 220 meters over 62.5/125µm OM1 multimode fiber. The 'D' suffix denotes DOM (Digital Optical Monitoring) support, enabling real-time diagnostics such as temperature, voltage, TX power, and RX power — a critical feature for proactive network management and troubleshooting.
This refurbished unit has been professionally inspected and tested to ensure full functional compliance with Cisco specifications, making it an excellent value-driven choice for network expansions, lab environments, or cost-sensitive deployments. Every refurbished transceiver offered by WhaleyComm undergoes quality verification before shipping, so you can deploy with confidence. Whether you are upgrading an existing infrastructure or building out a new network segment, the Cisco GLC-SX-MMD delivers proven Gigabit performance at a fraction of the cost of new.
Technical Specifications
Data Rate
1 Gbps (1000BASE-SX)
Max Range (50/125µm OM2)
550 meters
Max Range (62.5/125µm OM1)
220 meters
Digital Optical Monitoring (DOM)
Yes
Ideal Use Cases
Enterprise Campus Distribution Layer
Deploy the GLC-SX-MMD to interconnect distribution and access layer switches across campus buildings using existing multimode fiber infrastructure. Its 550-meter reach over OM2 fiber makes it ideal for intra-building backbone links.
Data Center Top-of-Rack Connectivity
Use this SFP transceiver to provide reliable 1G multimode uplinks between top-of-rack switches and aggregation switches within a data center. DOM support enables proactive monitoring of optical performance to minimize unplanned downtime.
Network Lab and Test Environments
The refurbished GLC-SX-MMD offers a cost-effective solution for building out lab, staging, or development network environments where full Gigabit SFP functionality is required. Its lower price point allows teams to scale test infrastructure without significant capital expenditure.
What's Included
✔ Cisco GLC-SX-MMD Refurbished SFP Transceiver Module
✔ Duplex LC Fiber Connector
✔ Protective Dust Cap
✔ Basic Functionality Testing Verification
Lifetime Warranty - No Time Limits. No Questions.
Every WhaleyComm unit ships with a Lifetime Warranty. If it fails under normal operating conditions at any point, we replace it. 25 years, 5,000+ customers.