Juniper Networks QDD-8x50G-0.5M Compatible 400G QSFP-DD 8 x 50G PAM4 to 8 x 50G SFP56 50G PAM4 Passive Copper Breakout Cable, 0.5m (2ft)

This page covers one precise cable-schedule item: Juniper Networks QDD-8x50G-0.5M in 0.5m (2ft), supporting 400G operation through QSFP-DD to 8x SFP56. The complete DAC assembly is identified separately from other lengths and includes verified specifications, change-control-friendly ordering details and live-link factory checks.
OEM Part Number: QDD-8x50G-0.5MHT Part Number: QDD-8x50G-0.5M
Product Highlights
- Compatible alternative to Juniper Networks QDD-8x50G-0.5M
- 400G connectivity at 400Gbps
- Interface configuration: QSFP-DD to 8x SFP56
- Fixed length and part number: 0.5m (2ft), QDD-8x50G-0.5M
- Cable construction: Passive Breakout DAC
- Conductor specification: 30AWG
- Maximum power consumption: 0.1W (QSFP-DD End)0.1W (SFP56 Per End)
- Minimum bend radius: 33.5mm
Specifications
| HT Part Number | QDD-8x50G-0.5M |
|---|---|
| Juniper Networks Compatible | QDD-8x50G-0.5M |
| Manufacturer | HT |
| Form Factor | QSFP-DD to 8x SFP56 |
| Max. Data Rate | 400Gbps |
| Media | Copper |
| Cable Type | Passive Breakout DAC |
| Minimum Bend Radius | 33.5mm |
| Wire AWG | 30AWG |
| Cable Length | 0.5m (2ft) |
| Jacket Material | PVC (OFNR) |
| Max. Power Consumption | 0.1W (QSFP-DD End)0.1W (SFP56 Per End) |
| Modulation Format | QSFP-DD-8x 50G-PAM4SFP56-50G-PAM4 |
| DDM/DOM | Not Supported |
| Commercial TemperatureRange | 0 to 70°C (32 to 158°F) |
| Protocols | QSFP-DD MSA, SFF-8432, IEEE 802.3bs-400GAUI-8, IEEE802.3cd-50GAUI-1, CMIS 4.0, SFF-8472 |
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.
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 0.5m (2ft) length is suited to closely aligned ports where excessive slack would obstruct airflow or complicate dressing. Measure the actual port-to-port path before choosing QDD-8x50G-0.5M; even a short assembly must retain the specified bend radius and should never be pulled tight behind the equipment.
Position Within the Length Range
QDD-8x50G-0.5M is the shortest of 6 verified length options in this family. It is the preferred choice when the port positions are close and cable slack must be kept to a minimum. The next option is QDD-8x50G-1M at 1m (3ft), adding 0.5m for a less direct routing path; selecting it unnecessarily would leave more cable to dress.
Structured Pathways and Serviceability
Treat the direct-attach assembly as part of the permanent pathway plan even when the link is expected to be temporary. Follow the intended horizontal and vertical managers, maintain the specified bend radius and leave service access around both ports. A small, supported service allowance is preferable to excess slack concealed inside a rack or placed under cable-tie pressure. For this assembly, the listed conductor specification is 30AWG; the minimum bend radius is 33.5mm; the stated power consumption is 0.1W (QSFP-DD End)0.1W (SFP56 Per End); the jacket material is PVC (OFNR).
Signal and Lane Configuration
The listed modulation format is QSFP-DD-8x 50G-PAM4SFP56-50G-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.
Power and Thermal Planning
The rated power consumption is 0.1W (QSFP-DD End)0.1W (SFP56 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 30AWG conductors, PVC (OFNR) jacket, minimum bend radius 33.5mm. 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 determined by the host interface and protocol support. Listed interface and protocol references include QSFP-DD MSA, SFF-8432, IEEE 802.3bs-400GAUI-8, IEEE802.3cd-50GAUI-1, CMIS 4.0, SFF-8472. Confirm that the host firmware and port configuration support the same operating mode.
Breakout Port Mapping
The QSFP-DD to 8x SFP56 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.
Ordering Information
Include the part number, fixed length, quantity and required pathway or rack grouping in the order information. The host model and firmware release are useful for change-controlled deployments. Different lengths should remain separate order lines so delivered labels and packing records agree with the pathway plan. Keep QDD-8x50G-0.5M associated with 0.5m (2ft) throughout the order and receiving record.
Juniper Networks Compatibility and Factory Testing
Verification covers the physical connectors, expected host identity and an operating link with available diagnostic indications. We distinguish this complete check from a simple continuity test. Platform model and software release can be reviewed in advance where the installation has strict documentation or change-control requirements. The check includes link stability and diagnostic indications, followed by a final inspection of both ends.
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
After connector inspection and link verification, the assembly is coiled without tight bends and packed with end protection. Labels can cross-reference the customer cable schedule, OEM part number and length. This supports both receiving checks and later moves, adds or changes. Volume orders can include customer references on the labels and carton list.
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-8x50G-0.5M.
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.
QDD-8x50G-0.5M