Cisco QDD-4ZQ100-CU2.5M Compatible 400G QSFP-DD 8 x 50G PAM4 to 4 x 100G QSFP56 2 x 50G PAM4 Passive Copper Breakout Cable, 2.5m (8ft)
For project documentation, Cisco QDD-4ZQ100-CU2.5M and this cable’s physical length should be recorded together. The product described here is a 2.5m (8ft) DAC assembly for 400G links, using QSFP-DD to 4x QSFP56. Its OEM cross-reference, HT part number, specification table and packing options support traceable ordering and installation records.
OEM Part Number: QDD-4ZQ100-CU2.5MHT Part Number: QDD-4ZQ100-CU2.5M
Product Highlights
- Compatible alternative to Cisco QDD-4ZQ100-CU2.5M
- 400G connectivity at 400Gbps
- Interface configuration: QSFP-DD to 4x QSFP56
- Fixed length and part number: 2.5m (8ft), QDD-4ZQ100-CU2.5M
- Conductor specification: 28AWG
- Maximum power consumption: 0.1W (QSFP-DD End)0.1W (QSFP56 Per End)
- Minimum bend radius: 41mm
- Operating temperature: 0 to 70°C (32 to 158°F)
Specifications
| HT Part Number | QDD-4ZQ100-CU2.5M |
|---|---|
| Cisco Compatible | QDD-4ZQ100-CU2.5M |
| Manufacturer | HT |
| Form Factor | QSFP-DD to 4x QSFP56 |
| Max. Data Rate | 400Gbps |
| Minimum Bend Radius | 41mm |
| Wire AWG | 28AWG |
| Cable Length | 2.5m (8ft) |
| Jacket Material | PVC |
| Media | Copper |
| Modulation Format | QSFP-DD-8x 50G-PAM4QSFP56-2x 50G-PAM4 |
| Commercial Temperature Range | 0 to 70°C (32 to 158°F) |
| Power Supply | 3.3V |
| Protocols | SFF-8665, QSFP-DD MSA, IEEE802.3bj, IEEE802.3 cd |
| Max. Power Consumption | 0.1W (QSFP-DD End)0.1W (QSFP56 Per End) |
| Application | 400G Ethernet |
Signal and Lane Configuration
The listed modulation format is QSFP-DD-8x 50G-PAM4QSFP56-2x 50G-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.
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 28AWG; the minimum bend radius is 41mm; the stated power consumption is 0.1W (QSFP-DD End)0.1W (QSFP56 Per End); the jacket material is PVC.
Power and Thermal Planning
The rated power consumption is 0.1W (QSFP-DD End)0.1W (QSFP56 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 28AWG conductors, PVC jacket, minimum bend radius 41mm. 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.
Network and Protocol Considerations
The intended application is 400G Ethernet. Listed interface and protocol references include SFF-8665, QSFP-DD MSA, IEEE802.3bj, IEEE802.3 cd. Confirm that the host firmware and port configuration support the same operating mode.
Breakout Port Mapping
The QSFP-DD to 4x QSFP56 configuration divides the high-speed interface into multiple lower-speed connections. Verify the upstream lane assignment, downstream port speeds and breakout setting on the host before connecting the assembly. Each branch must attach to the correct remote interface.
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-4ZQ100-CU2.5M reaches both ports without tension at either connector.
Position Within the Length Range
QDD-4ZQ100-CU2.5M occupies the middle of this family between QDD-4ZQ100-CU2M at 2m (7ft) and QDD-4ZQ100-CU3M 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.
Cisco 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 Cisco cable?
No. It is an HT-manufactured compatible alternative for equipment that specifies Cisco QDD-4ZQ100-CU2.5M.
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-4ZQ100-CU2.5M 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.
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. Keep QDD-4ZQ100-CU2.5M associated with 2.5m (8ft) throughout the order and receiving record.
Shipping and Lead Time
Standard configurations normally ship within one to three working days, while production quantities are confirmed with the order. Worldwide courier services are available, with air or sea freight for consolidated shipments; freight-collect delivery and coordination with a customer’s logistics provider can be arranged.
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.
