Arista Networks QDD-ER8-400G Compatible 400G QSFP-DD ER8 Transceiver Module

The QDD-ER8-400G compatible module serves equipment requiring a 400G QSFP-DD interface with 1310nm optics and a 40km rating. Connection is through Duplex LC/UPC. Product data, application guidance and factory verification are presented together to support high-density deployments balance optical performance, port access and thermal planning.
OEM Part Number: QDD-ER8-400GHT Part Number: QDD-ER8-400G
Product Highlights
- Compatible alternative to Arista Networks QDD-ER8-400G
- 400G connectivity at 425Gbps
- Optical wavelength: 1310nm
- Specified reach: 40km
- Duplex LC/UPC / SMF interface
- Digital diagnostic monitoring: Supported
- Operating temperature: 0 to 70°C (32 to 158°F)
Specifications
| HT Part Number | QDD-ER8-400G |
|---|---|
| Manufacturer | HT |
| Form Factor | QSFP-DD |
| Max Data Rate | 425Gbps |
| Wavelength | 1310nm |
| Max. Cable Distance | 40km |
| Connector | Duplex LC/UPC |
| Media | SMF |
| Transmitter Type | LWDM EML |
| Receiver Type | APD |
| TX Power | -0.6~5.6dBm |
| Minimum Receiver Power | -16.1dBm(SECQ–17.5dBm) |
| Power Budget | 15.5dB |
| Receiver Overload | -3.4dB |
| Max. Power Consumption | 14W |
| Extinction Ratio | 6dB |
| DDM/DOM | Supported |
| Commercial Temperature Range | 0 to 70°C (32 to 158°F) |
| Modulation (Electrical) | 8x50G-PAM4 |
| Modulation (Optical) | 8x50G-PAM4 |
| DSP | TX and RX |
| Host FEC | Supported |
| Protocols | QSFP-DD MSA Compliant |
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.
The single-mode link budget should include fiber attenuation, connectors, splices and panels over the intended 40km route. Keep the Duplex LC/UPC interface clean and match the remote optical standard. Consider receiver overload as well as insufficient power on short links.
Quality Assurance and Packaging
Each QDD-ER8-400G 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.
Optical Acceptance, Diagnostics and Handling
For this model, the specified transmit-power range is -0.6~5.6dBm; the stated optical power budget is 15.5dB. 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.
High-Density Port and Thermal Planning
In a densely populated chassis, connector access and airflow form part of the optical-link design. Confirm that neighboring modules and patch leads leave room for latch operation, and include listed power consumption in the host thermal budget. Assess port density together with fiber management. For this model, the principal parameters are data rate 425Gbps, wavelength 1310nm, rated reach 40km.
Ordering Information
When ordering, specify QDD-ER8-400G, QDD-ER8-400G, 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.
Arista Networks Compatibility and Factory Testing
Factory verification starts with the expected QDD-ER8-400G 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.
Frequently Asked Questions
Is this an original Arista Networks transceiver?
No. It is an HT-manufactured compatible alternative for equipment that specifies QDD-ER8-400G, not an original Arista Networks-branded module.
Which fiber and connector are required?
Use Duplex LC/UPC with SMF. The specified maximum reach is 40km, 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.
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.
10/100BASE-T SFP