Juniper Networks QDD-400G-DAC-2P5M Compatible 400G QSFP-DD 8 x 50G PAM4 Passive Copper Twinax Cable, 2.5m (8ft)
For buyers working from an equipment parts list, QDD-400G-DAC-2P5M identifies more than a connector style. It refers here to a 2.5m (8ft) DAC cable for Juniper Networks hosts, supporting 400G operation with QSFP-DD to QSFP-DD. The sections below separate the OEM cross-reference, physical specification and HT factory checks for straightforward purchasing review.
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.
Procurement and Port-Mapping Review
A useful purchase order should identify the host platform, the expected OEM code and the exact cable length as separate pieces of information. This prevents a physically similar assembly from being substituted when the port identification or reach is different. For mixed-length installations, prepare one order line per part number and reconcile each delivered cable with its intended pair of ports. 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
Our procurement-oriented compatibility check begins with the OEM reference and ends with a live host link. We record the physical length separately from the identification configuration, so the cable supplied for this page remains the stated version rather than a generic length substitute. The check includes link stability and diagnostic indications, followed by a final inspection of both ends.
Ordering Information
For a clear bill of materials, quote the OEM reference, HT part number, length and quantity on the same line. Add the switch or server model and software release when a pre-order review is required; project labels can repeat those details for receiving and installation teams. Quantity and any labeling instructions should be attached specifically to QDD-400G-DAC-2P5M.
Quality Assurance and Packaging
Before packing, the assembly is checked for connector condition, identification and link operation. Cables for multi-line orders can be labelled and grouped by part number, making it easier to match each length to the procurement record without opening every protective bag. Standard protective packing is used by default, with project documentation arranged when requested.
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 different brands be connected with the same assembly?
Only where both hosts explicitly support the complete interface and compatibility arrangement. Document each end and select the appropriate brand-specific product when required.
Does this order code cover multiple lengths?
No. QDD-400G-DAC-2P5M refers here to 2.5m (8ft). Every other verified length has a separate part number and page in the length list.
Are separate transceivers or patch leads required?
No. This is one complete direct-attach assembly. The ends are not detachable modules and should not be separated from the cable.
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.