Cisco QDD-400G-SR4.2-BD Compatible 400G QSFP-DD SR4.2 Transceiver Module

Product Highlights

• Compatible alternative to Cisco QDD-400G-SR4.2-BD
• 400G connectivity at 425Gbps
• Optical wavelength: 850nm,910nm
• Specified reach: 70m on OM3 / 150m on OM5
• MTP/MPO-12 (UPC) / MMF interface
• Digital diagnostic monitoring: Supported
• Operating temperature: 0 to 70°C (32 to 158°F)

Specifications

Applications and Optical Link Design

Typical deployments include switch-to-switch, switch-to-server and aggregation links inside a data hall or between adjacent equipment rooms. The MTP/MPO-12 (UPC) interface connects to the specified multimode cabling, and the stated reach depends on fiber grade and link loss. Keep this interface on the matching multimode optical standard rather than connecting it directly to a single-mode wavelength or reach variant.

Before deployment, check the host port type, supported data rate and firmware requirements. The 400G interface configuration must match the remote equipment; sharing a QSFP-DD housing alone does not make two transceiver types interoperable.

The multimode channel should use the fiber grade associated with the stated 70m on OM3 / 150m on OM5 reach. Keep the MTP/MPO-12 (UPC) end faces clean and avoid tight bends. Different multimode standards are not interchangeable merely because they share a connector.

Cisco Compatibility and Factory Testing

The module is checked for host recognition as QDD-400G-SR4.2-BD, 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.

Optical Acceptance, Diagnostics and Handling

For this model, the specified transmit-power range is -6.5dBm~4dBm; the stated optical power budget is 2dB. 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. Diagnostic monitoring is listed as Supported. 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.

Structured Fiber Pathways and Serviceability

Treat the transceiver as part of the complete channel. Follow the intended patch-panel route, maintain bend control and leave service access around the port. Confirm connector polish and fiber type at every mated pair; a documented service allowance is preferable to excess slack concealed inside a rack. For this model, the principal parameters are data rate 425Gbps, wavelength 850nm,910nm, rated reach 70m on OM3 / 150m on OM5.

Ordering Information

Quote HT part number QDD-SR4.2-400G together with OEM reference QDD-400G-SR4.2-BD and quantity. Add the host model and software release when pre-order verification is required. 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.

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.

Frequently Asked Questions