Cisco QDD-SR4-400G Compatible 400G QSFP-DD SR4 Transceiver Module

Product Highlights

• Compatible alternative to Cisco QDD-SR4-400G
• 400G connectivity at 400Gbps
• Optical wavelength: 850nm
• Specified reach: 30m on OM3 / 50m on OM4
• MPO-12/APC / MMF interface
• Digital diagnostic monitoring: Supported
• Operating temperature: 0 to 70°C (32 to 158°F)

Specifications

Rack Integration and Service Access

Plan the fiber route before removing connector protection. The patch lead should follow its manager without pulling on the transceiver, while leaving space to release the latch and service adjacent ports. Protect the end face until final connection and avoid tight bends immediately behind warm exhaust air. For this model, the principal parameters are data rate 400Gbps, wavelength 850nm, rated reach 30m on OM3 / 50m on OM4.

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 MPO-12/APC 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 30m on OM3 / 50m on OM4 reach. Keep the MPO-12/APC end faces clean and avoid tight bends. Different multimode standards are not interchangeable merely because they share a connector.

Optical Acceptance, Diagnostics and Handling

For this model, the specified transmit-power range is -4.6~4dBm; the stated optical power budget is 1.8dB. A sound acceptance record includes link state, diagnostic temperature, supply voltage and transmit or receive levels where the host exposes them. Compare the readings with the stated ranges rather than treating any received light as proof of adequate margin. Persistent alarms or borderline values should trigger an end-face and complete-channel inspection. 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.

Quality Assurance and Packaging

Quality control covers the optical or electrical interface, host identification and operating link. The verified unit is then individually protected and cartoned. Customer references, rack groups and project packing lists can be added for volume orders.

Cisco Compatibility and Factory Testing

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

Ordering Information

When ordering, specify QDD-SR4-400G, QDD-SR4-400G, 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.