Juniper Networks QDD-400G-DAC-2P5M Compatible 400G QSFP-DD 8 x 50G PAM4 Passive Copper Twinax Cable, 2.5m (8ft)

The assembly listed here is the 2.5m (8ft) member of the QDD-400G-DAC-2P5M product family for Juniper Networks equipment. It provides 400G DAC connectivity through QSFP-DD to QSFP-DD. Project teams can use the detailed table, related references and documentation-oriented packing information to keep each delivered cable aligned with its planned endpoints.
OEM Part Number: QDD-400G-DAC-2P5MHT Part Number: QDD-400G-DAC-2P5M
Product Highlights
- Compatible alternative to Juniper Networks QDD-400G-DAC-2P5M
- 400G connectivity at 400Gbps
- Interface configuration: QSFP-DD to QSFP-DD
- Fixed length and part number: 2.5m (8ft), QDD-400G-DAC-2P5M
- Cable construction: Passive Twinax
- Conductor specification: 26AWG
- Maximum power consumption: 0.1W Per End
- Minimum bend radius: 57mm
Specifications
| HT Part Number | QDD-400G-DAC-2P5M |
|---|---|
| Juniper Networks Compatible | QDD-400G-DAC-2P5M |
| Manufacturer | HT |
| Form Factor | QSFP-DD to QSFP-DD |
| Max. Data Rate | 400Gbps |
| Media | Copper |
| Cable Type | Passive Twinax |
| Cable Length | 2.5m (8ft) |
| Wire AWG | 26AWG |
| Minimum Bend Radius | 57mm |
| 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 |
Juniper Deployment Reference
Juniper platform documentation distinguishes straight QSFP28 DAC or AOC connections from DACBO and AOCBO breakout operation. On channelized systems, the host port must be configured for the required breakout mode. Match this HT compatible cable to the exact Juniper part number and the intended platform configuration.
Network and Protocol Considerations
The intended application is 400G Ethernet. Listed interface and protocol references include IEEE 802.3cd, QSFP-DD MSA, CMIS 4.0. Confirm that the host firmware and port configuration support the same operating mode.
Passive Copper Operation
A passive DAC has no separate optical conversion stage. Its low-power, low-latency operation is useful for short equipment links, but the assembly must remain within the length and signaling mode accepted by both hosts.
Length Selection and Installation Planning
The 2.5m (8ft) version is useful when a two-metre run would leave insufficient working slack. Before installation, check the complete horizontal and vertical path so that QDD-400G-DAC-2P5M reaches both ports without tension at either connector.
Position Within the Length Range
QDD-400G-DAC-2P5M occupies the middle of this family between QDD-400G-DAC-2M at 2m (7ft) and QDD-400G-DAC-3M at 3m (10ft). It adds 0.5m over the shorter option for extra routing clearance, while the next longer version adds another 0.5m. Measure the managed path and choose this version when its reach is sufficient without creating the slack associated with the longer assembly.
Project Documentation and Cable Identification
Large deployments are easier to audit when the order code, physical length and endpoint record agree. Keep the OEM reference in the compatibility document and use the HT part number on the packing list. Where several lengths arrive together, labels and carton groups can be arranged by rack or port plan so installers do not have to identify cables by appearance alone. For this assembly, the listed conductor specification is 26AWG; the minimum bend radius is 57mm; the stated power consumption is 0.1W Per End; the jacket material is PET.
Signal and Lane Configuration
The listed modulation format is 8x 50Gbps PAM4. Both host interfaces must be configured for the same aggregate rate and lane arrangement. A connector that fits mechanically does not by itself guarantee that the remote port supports this encoding or breakout mode.
Power and Thermal Planning
The rated power consumption is 0.1W Per End. Include this load in the host-port power and thermal budget, especially in densely populated switches. Maintain front-panel clearance and do not bundle the cable so tightly that it obstructs airflow around the connectors.
Cable Construction and Routing
This assembly uses 26AWG conductors, PET jacket, minimum bend radius 57mm. These mechanical characteristics affect how the cable should be dressed behind the equipment. Avoid sharp edges, excessive ties and repeated tight bends close to the connector boots.
Juniper Networks Compatibility and Factory Testing
Factory verification links the compatibility identity to the exact physical assembly described on this page. Identification, connector condition and live link behavior are checked before packing. Customers can submit equipment and firmware details with the project documentation for a more specific pre-order compatibility review. The check includes link stability and diagnostic indications, followed by a final inspection of both ends.
Frequently Asked Questions
Is this an original Juniper Networks cable?
No. It is an HT-manufactured compatible alternative for equipment that specifies Juniper Networks QDD-400G-DAC-2P5M.
Can excess cable be folded into a compact bundle?
No. Use a supported, bend-safe service loop and observe the listed minimum bend radius. Do not crease the cable or tighten ties around the connector boots.
Will any matching connector operate at the same speed?
Not necessarily. Both hosts must support the stated rate, identification, lane mapping and any required breakout configuration; mechanical compatibility alone is insufficient.
What details assist a compatibility review?
Provide the equipment manufacturer, model, port type, hardware revision and software release, together with the OEM reference, required length and quantity.
Ordering Information
Use the listed HT part number for ordering and retain the OEM reference as the host-compatibility cross-reference. Send quantities by length, along with any rack-based packing or label instructions. If the project has mixed equipment, include the host model for each group rather than relying only on the aggregate cable rate. Quantity and any labeling instructions should be attached specifically to QDD-400G-DAC-2P5M.
Shipping and Lead Time
Available stock is generally dispatched within one to three working days after order confirmation, with production lead times advised for larger quantities. Delivery can be arranged by courier, air freight or sea freight, and goods may instead be handed to an appointed forwarder or shipped on the customer’s courier account.
Quality Assurance and Packaging
Inspection and link testing are completed before the cable enters its protective packaging. Project orders can be packed and labelled by length, rack or customer reference, with packing documentation that makes received quantities straightforward to reconcile against the installation schedule. Standard protective packing is used by default, with project documentation arranged when requested.
