Cisco GLC-BX120-D Compatible 1G SFP Transceiver Module

Product Highlights

• Compatible alternative to Cisco GLC-BX120-D
• 1G connectivity at 1.25Gbps
• Optical wavelength: 1550nm-TX/1490nm-RX
• Specified reach: 120km
• Simplex LC / SMF interface
• Operating temperature: 0 to 70°C (32 to 158°F)
• Factory compatibility verification and optical performance testing before shipment

Specifications

Applications and Optical Link Design

This BiDi interface is useful where only one fiber strand is available between two sites or racks. It must be paired with the complementary wavelength direction: one end transmits on the wavelength that the other end receives. Verify the paired part number, connector polish and fiber plant before installation, and measure link loss against the specified optical budget.

Before deployment, check the host port type, supported data rate and firmware requirements. The 1G interface configuration must match the remote equipment; sharing a SFP housing alone does not make two transceiver types interoperable.

BiDi operation saves a fiber strand but makes wavelength orientation critical. Record the part installed at each end and check its paired receive wavelength. The 120km rating still depends on total channel loss, including connectors and splices.

Quality Assurance and Packaging

Each GLC-BX120-D compatible module is inspected, powered up and functionally checked before protective packing. Dust caps and individual trays shield the interface during transport. Customer references, rack groups and project packing lists can be added for volume orders.

Optical Acceptance, Diagnostics and Handling

For this model, the specified transmit-power range is -1~4dBm; receiver sensitivity is < -31dBm. During commissioning, record the host diagnostic readings after the link has stabilized and compare them with those limits. DOM values are useful operational indicators, but they do not replace calibrated optical measurements when a link is marginal. Investigate unexpected loss through connector inspection, cleaning and a channel measurement before replacing the module. 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.

Data-Center Optical Design and Airflow

Select the module by optical standard, reach and rack layout. Check the complete fiber channel, including panels and connectors, and keep dense bundles from blocking front-panel airflow. Account for listed power consumption and preserve enough space to remove a module without disturbing adjacent links. For this model, the principal parameters are data rate 1.25Gbps, wavelength 1550nm-TX/1490nm-RX, rated reach 120km.

Ordering Information

Use GLC-BX120-D as the compatibility cross-reference and SFP-1G54-BX120 as the HT ordering identity. Keep other reaches or wavelength directions on separate order lines. Neutral labels, customer packaging and project-specific compatibility review are available on request.

Cisco Compatibility and Factory Testing

The module is checked for host recognition as GLC-BX120-D, link establishment and diagnostic reporting. Physical cage fit alone is not treated as evidence of compatibility. Equipment model, hardware revision and software release can be reviewed before dispatch where platform behavior is uncertain.

Frequently Asked Questions

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.