Arista Networks QDD-400G-XDR4 Compatible 400G QSFP-DD XDR4 Transceiver Module
The QDD-400G-XDR4 compatible module serves equipment requiring a 400G QSFP-DD interface with 1310nm optics and a 2km rating. Connection is through MPO-12/APC. Product data, application guidance and factory verification are presented together to support project teams keep OEM references, delivery records and port schedules aligned.
OEM Part Number: QDD-400G-XDR4HT Part Number: QDD-XDR4-400G
Product Highlights
- Compatible alternative to Arista Networks QDD-400G-XDR4
- 400G connectivity at 400Gbps
- Optical wavelength: 1310nm
- Specified reach: 2km
- MPO-12/APC / SMF interface
- Digital diagnostic monitoring: Supported
- Operating temperature: 0 to 70°C (32 to 158°F)
Specifications
| Arista Networks Compatible | QDD-400G-XDR4 |
|---|---|
| Manufacturer | HT |
| HT Part Number | QDD-XDR4-400G |
| Form Factor | QSFP-DD |
| Max. Data Rate | 400Gbps |
| Wavelength | 1310nm |
| Max. Cable Distance | 2km |
| Connector | MPO-12/APC |
| Media | SMF |
| Transmitter Type | 1310nm EML |
| Receiver Type | PIN |
| TX Power | -3.1~4dBm |
| Minimum Receiver Power | -7.1dBm |
| Power Budget | 4dB |
| Receiver Overload | 4dBm |
| 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 |
| DSP | TX and RX |
| Inbuilt FEC | No |
| Core Size | G.652/9um |
| Packaging Technology | COB (Chip on Board) Packaging |
| Protocols | QSFP-DD MSA, CMIS.5.0, IEEE 802.3bs |
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 400Gbps, wavelength 1310nm, rated reach 2km.
Arista Networks Compatibility and Factory Testing
Factory verification starts with the expected QDD-400G-XDR4 identity and finishes with an operating host link. EEPROM data, diagnostic visibility and the stated optical parameters are assessed together. 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 2km. Inspect every MPO-12/APC 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 -3.1~4dBm; the stated optical power budget is 4dB. Digital diagnostics make later maintenance easier when baseline values are captured at installation. Save the initial readings with the port and OEM reference, then investigate meaningful changes rather than reacting to a single transient value. Diagnostic support depends on the host as well as the module, so unavailable fields should be confirmed with the platform documentation. 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 Arista Networks transceiver?
No. It is an HT-manufactured compatible alternative for equipment that specifies QDD-400G-XDR4, not an original Arista Networks-branded module.
Which fiber and connector are required?
Use MPO-12/APC with SMF. The specified maximum reach is 2km, 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
Use QDD-400G-XDR4 as the compatibility cross-reference and QDD-XDR4-400G 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.
