Cisco GLC-LH-SMD Compatible 1G SFP Transceiver Module
Built for hosts recognizing GLC-LH-SMD, this HT-manufactured SFP module delivers 1G transmission at 1310nm. Its rated reach is 10km on SMF, with Duplex LC as the physical interface. The specifications and engineering guidance below support field technicians install, maintain and identify the exact compatible module, while keeping HT manufacture separate from the OEM cross-reference.
OEM Part Number: GLC-LH-SMDHT Part Number: SFP1G-LX-31
Product Highlights
- Compatible alternative to Cisco GLC-LH-SMD
- 1G connectivity at 1.25Gbps
- Optical wavelength: 1310nm
- Specified reach: 10km on SMF
- Duplex LC / SMF interface
- Operating temperature: -40 to 85°C (-40 to 185°F)
- Factory compatibility verification and optical performance testing before shipment
Specifications
| Cisco Compatible | GLC-LH-SMD |
|---|---|
| Manufacturer | HT |
| HT Part Number | SFP1G-LX-31 |
| Form Factor | SFP |
| Max. Data Rate | 1.25Gbps |
| Wavelength | 1310nm |
| Max. Cable Distance | 10km@SMF |
| Connector | Duplex LC |
| Optical Components | FP 1310nm |
| Media | SMF |
| DOM Support | Yes |
| TX Power | -9.5~-3dBm |
| Receiver Sensitivity | < -23dBm |
| Industrial Temperature Range | -40 to 85°C (-40 to 185°F) |
| Protocols | SFF-8472 MSA Compliant, IEEE 802.3ah-2004 |
Field Installation and Maintenance
Inspect the connector and patch lead before installation, then support the fiber without pulling on the module housing. Release the latch properly during maintenance and keep dust protection on unused interfaces. If a module is removed for later use, retain its part-number label and record its original port. For this model, the principal parameters are data rate 1.25Gbps, wavelength 1310nm, rated reach 10km on SMF.
Applications and Optical Link Design
Use this module for equipment interconnection over the specified single-mode fiber plant, including enterprise backbone, campus, metro or data-center interconnect links according to its rated distance. Confirm that both ends use the same optical standard and wavelength plan, and allow for connector, splice and patch-panel loss within the stated power budget.
The industrial temperature rating makes this version appropriate for controlled outdoor cabinets, transport nodes and other installations exposed to wider ambient temperature variation. Adequate airflow, protected cable routing and host-platform temperature limits still apply.
The single-mode link budget should include fiber attenuation, connectors, splices and panels over the intended 10km on SMF route. Keep the Duplex LC interface clean and match the remote optical standard. Consider receiver overload as well as insufficient power on short links.
Optical Acceptance, Diagnostics and Handling
For this model, the specified transmit-power range is -9.5~-3dBm; receiver sensitivity is < -23dBm. Digital diagnostics make later maintenance easier when baseline values are captured at installation. Save the initial readings with the port and OEM reference, then investigate meaningful changes rather than reacting to a single transient value. Diagnostic support depends on the host as well as the module, so unavailable fields should be confirmed with the platform documentation. Before every insertion, keep dust caps in place until the patch lead is ready, avoid touching the optical end face and use an appropriate inspection and cleaning procedure. Do not look into an active optical interface.
Quality Assurance and Packaging
Before packing, the module receives interface inspection, identification and link checks. Protective packaging avoids pressure on the connector and latch. Customer references, rack groups and project packing lists can be added for volume orders.
Cisco Compatibility and Factory Testing
Compatibility testing for GLC-LH-SMD combines identification with a live link and available transmit, receive and alarm information. Connector condition is inspected separately. Equipment model, hardware revision and software release can be reviewed before dispatch where platform behavior is uncertain.
Frequently Asked Questions
Is this an original Cisco transceiver?
No. It is an HT-manufactured compatible alternative for equipment that specifies GLC-LH-SMD, not an original Cisco-branded module.
Which fiber and connector are required?
Use Duplex LC with SMF. The specified maximum reach is 10km on SMF, subject to fiber quality and total link loss.
Can it be mixed with another wavelength or reach version?
Only when the two ends share the same optical standard, wavelength plan and supported data rate. Check the exact part numbers and link budget rather than relying only on the module form factor.
Ordering Information
When ordering, specify GLC-LH-SMD, SFP1G-LX-31, quantity and intended host platform. Project labels can repeat these details for receiving and asset records. Neutral labels, customer packaging and project-specific compatibility review are available on request.
Shipping and Lead Time
Standard configurations normally ship within one to three working days, with production lead times confirmed for larger quantities. International courier, air freight and sea freight are available; customer courier accounts and nominated forwarders are accepted.
