Cisco QDD-400G-LR4-S Compatible 400G QSFP-DD LR4 Transceiver Module

This Cisco QDD-400G-LR4-S compatible transceiver provides 400G connectivity in a hot-swappable QSFP-DD package. Its optical design operates at 1271nm, 1291nm, 1311nm, and 1331nm for up to 10km, using Duplex LC/UPC. Complete parameters and related OEM references help project teams keep OEM references, delivery records and port schedules aligned.
OEM Part Number: QDD-400G-LR4-SHT Part Number: QDD-LR4-400G
Product Highlights
- Compatible alternative to Cisco QDD-400G-LR4-S
- 400G connectivity at 425Gbps (4x 106.25Gbps)
- Optical wavelength: 1271nm, 1291nm, 1311nm, and 1331nm
- Specified reach: 10km
- Duplex LC/UPC / SMF interface
- Digital diagnostic monitoring: Supported
- Operating temperature: 0 to 70°C (32 to 158°F)
Specifications
| Cisco Compatible | QDD-400G-LR4-S |
|---|---|
| Manufacturer | HT |
| HT Part Number | QDD-LR4-400G |
| Form Factor | QSFP-DD |
| Max. Data Rate | 425Gbps (4x 106.25Gbps) |
| Wavelength | 1271nm, 1291nm, 1311nm, and 1331nm |
| Max. Cable Distance | 10km |
| Connector | Duplex LC/UPC |
| Media | SMF |
| Transmitter Type | CWDM EML |
| Receiver Type | PIN |
| TX Power | -2.7~5.1dBm |
| Minimum Receiver Power | -9.0dBm |
| Power Budget | 6.3dB |
| Receiver Overload | 5.1dBm |
| Max. Power Consumption | 9W |
| Extinction Ratio | 3.5dB |
| DDM/DOM | Supported |
| Commercial Temperature Range | 0 to 70°C (32 to 158°F) |
| Modulation (Electrical) | 8x50G-PAM4 |
| Modulation (Optical) | 4x100G-PAM4 |
| CDR (Clock and Data Recovery) | TX & RX Built-in DSP |
| Inbuilt FEC | No |
| Core Size | G.652/9um |
| Packaging Technology | COB (Chip on Board) Packaging |
| Protocols | QSFP-DD MSA HW Rev 5.1, QSFP-DD, CMIS Rev 5.0, IEEE 802.3cu, 100G Lambda MSA |
Project Documentation and Traceability
Large deployments are easier to audit when the order code, optical standard and endpoint record agree. Keep the OEM reference in the compatibility document and the HT part number on the packing list. Labels and carton groups can be arranged by rack or port plan so installers need not identify modules by appearance. For this model, the principal parameters are data rate 425Gbps (4x 106.25Gbps), wavelength 1271nm, 1291nm, 1311nm, and 1331nm, rated reach 10km.
Cisco Compatibility and Factory Testing
The module is checked for host recognition as QDD-400G-LR4-S, 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.
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.
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.
Before commissioning, measure the complete single-mode channel against the stated budget for 10km. Inspect every Duplex LC/UPC connection and record diagnostic power where supported. Both ends must agree on rate, wavelength and optical standard.
Optical Acceptance, Diagnostics and Handling
For this model, the specified transmit-power range is -2.7~5.1dBm; the stated optical power budget is 6.3dB. 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.
Frequently Asked Questions
Is this an original Cisco transceiver?
No. It is an HT-manufactured compatible alternative for equipment that specifies QDD-400G-LR4-S, not an original Cisco-branded module.
Which fiber and connector are required?
Use Duplex LC/UPC with SMF. The specified maximum reach is 10km, 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 QDD-400G-LR4-S, QDD-LR4-400G, 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.
Quality Assurance and Packaging
Each QDD-400G-LR4-S 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.
