Juniper Networks QDD-400G-VSR4 Compatible 400G QSFP-DD SR4 Transceiver Module

Product Highlights

• Compatible alternative to Juniper Networks QDD-400G-VSR4
• 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

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.

Juniper Networks Compatibility and Factory Testing

The module is checked for host recognition as QDD-400G-VSR4, 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 -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.

Interoperability and Host Configuration

Check three layers before deployment: host acceptance of the module identity, port support for the stated rate, and a matching optical standard at the remote interface. For breakout operation, confirm lane configuration too. Similar-looking cages can behave differently across speeds and firmware settings. For this model, the principal parameters are data rate 400Gbps, wavelength 850nm, rated reach 30m on OM3 / 50m on OM4.

Ordering Information

Use QDD-400G-VSR4 as the compatibility cross-reference and QDD-400G-VSR4 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.

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