Juniper Networks QDD-400G-DAC Compatible 400G QSFP-DD 8 x 50G PAM4 Passive Copper Twinax Cable

A 400G direct-attached link depends on the correct host identity, interface mode and physical length. This page covers the Juniper Networks QDD-400G-DAC compatible DAC series in QSFP-DD to QSFP-DD, including 0.5m (2ft), 1m (3ft), 1.5m (5ft), 2m (7ft), 2.5m (8ft) and 3m (10ft). Each documented length-specific OEM reference is linked separately where an individual product page is available.
Series Part Number: QDD-400G-DACHT Part Number: QDD-400G-DAC
Product Highlights
- HT-manufactured compatible alternative for Juniper Networks QDD-400G-DAC
- 400G aggregate connectivity at 400Gbps
- Interface configuration: QSFP-DD to QSFP-DD
- Passive Twinax / Copper
- Length configurations covered: 0.5m (2ft), 1m (3ft), 1.5m (5ft), 2m (7ft), 2.5m (8ft) and 3m (10ft)
- Conductor specification: 30AWG
- Power consumption: 0.1W Per End
- Operating temperature: 0 to 70°C (32 to 158°F)
Available Lengths and Corresponding Part Numbers
The documented configurations are 0.5m (2ft), 1m (3ft), 1.5m (5ft), 2m (7ft), 2.5m (8ft) and 3m (10ft). Each link below opens the separate product page for that physical length and its corresponding OEM part number. Select the exact assembly required by the route and purchase order; custom project lengths can be discussed separately.
Compatible OEM Part Numbers
- QDD-400G-DAC-0.5M
- QDD-400G-DAC-1M
- QDD-400G-DAC-1.5M
- QDD-400G-DAC-2M
- QDD-400G-DAC-2P5M
- QDD-400G-DAC-3M
Specifications
| Juniper Networks Compatible | QDD-400G-DAC-0.5M |
|---|---|
| Manufacturer | HT |
| HT Part Number | QDD-400G-DAC |
| Form Factor | QSFP-DD to QSFP-DD |
| Max. Data Rate | 400Gbps |
| Media | Copper |
| Cable Type | Passive Twinax |
| Cable Length Options Covered | 0.5m (2ft), 1m (3ft), 1.5m (5ft), 2m (7ft), 2.5m (8ft) and 3m (10ft) |
| Wire AWG | 30AWG |
| Minimum Bend Radius | 33mm |
| Max. Power Consumption | 0.1W Per End |
| Jacket Material | PET |
| Commercial Temperature Range | 0 to 70°C (32 to 158°F) |
| Modulation Format | 8x 50Gbps PAM4 |
| Application | 400G Ethernet |
| Protocols | IEEE 802.3cd, QSFP-DD MSA, CMIS 4.0 |
Field Installation and Maintenance
Inspect the route and both connectors before installation, then support the cable without pulling on either connector housing. During maintenance, release the latch properly rather than using the cable as a handle. Keep protection on unused ends, and if the assembly is removed for later use, coil it loosely and record its part number so the same length can be returned to service. For this series, keep the interface rate, DAC construction and length-specific OEM reference together throughout that review.
Applications and Deployment
Passive twinax cables are commonly selected for short switch-to-switch, switch-to-server and accelerator connections within or between nearby racks. With no separate optical conversion stage, they offer a simple low-power physical link. The assembly must nevertheless remain within the length, signaling rate and qualification limits accepted by both hosts. For this series, the listed interface is QSFP-DD to QSFP-DD and the aggregate rate is 400G. The stated application is 400G Ethernet.
Cable Construction and Routing
The specification table records the conductor specification is 30AWG; the jacket material is PET; the minimum bend radius is 33mm; the operating temperature is 0 to 70°C (32 to 158°F); the power consumption is 0.1W Per End. Use those values when preparing the rack pathway and receiving checklist. Do not pull a connector by its cable, compress the run under tight ties or force excess length into a sharp coil. Connector protection should remain in place until the assembly is ready for insertion.
Quality Assurance and Packaging
The cable and both connectors are inspected before a functional link test. Connector protection and bend-safe packing reduce handling damage during transport and storage. Customer or site labels can be added for field inventories, with different lengths separated to simplify issue and return of spare assemblies. Both connector ends are inspected as part of the complete assembly, and protective packing is selected to avoid tight bends during transport and storage.
Juniper Networks Compatibility and Factory Testing
A field-ready cable needs both correct identification and a stable operating link. Our pre-packing check therefore includes the connectors, host recognition and link behavior. For equipment with uncertain revision history, providing the host model and software release helps identify compatibility requirements before the assembly reaches the installation site. Series-level inspection is followed by the exact length and OEM configuration selected for dispatch. Functional verification includes link establishment and diagnostic indications where the host exposes them.
Ordering Information
Request the cable by its exact part number and length, and state the equipment model if compatibility confirmation is needed. Site orders can list quantities by rack or installation team. Any requested label should retain the part number so a removed or spare cable can still be identified accurately. For this series, follow the corresponding length link, quote that exact OEM part number and keep different lengths on separate order lines. HT part number QDD-400G-DAC identifies the product family; the linked page provides the final length-specific identity.
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.
Frequently Asked Questions
Is this an original Juniper Networks cable?
No. It is an HT-manufactured compatible cable for equipment that specifies QDD-400G-DAC, not an original Juniper Networks-branded product.
Are different lengths and OEM part numbers separate products?
Yes. Where a length has its own OEM reference, follow the corresponding link above and order that exact part number on its own line. Do not substitute another length only because the connector arrangement is the same.
