Cisco QDD-400G-4Q4xNAO Compatible 400G QSFP-DD 8 x 50G PAM4 to 4 x 100G QSFP28 4 x 25G NRZ Active Optical Breakout Cable

A 400G direct-attached link depends on the correct host identity, interface mode and physical length. This page covers the Cisco QDD-400G-4Q4xNAO compatible AOC series in QSFP-DD to 4x QSFP28, including 3m (10ft). Each documented length-specific OEM reference is linked separately where an individual product page is available.
Series Part Number: QDD-400G-4Q4xNAOHT Part Number: QDD-400G-4Q4xNAO
Product Highlights
- HT-manufactured compatible alternative for Cisco QDD-400G-4Q4xNAO
- 400G aggregate connectivity at 400Gbps
- Interface configuration: QSFP-DD to 4x QSFP28
- Breakout AOC
- Length configurations covered: 3m (10ft)
- Power consumption: 10W (QSFP-DD End)5.5W (QSFP28 Per End)
Available Lengths and Corresponding Part Numbers
The documented series configuration is 3m (10ft). Use the relevant OEM reference below together with the HT identity and required length when requesting a quotation. If another length carries a different OEM part number, it must be reviewed and ordered as that distinct configuration.
Compatible OEM Part Numbers
- QDD-400G-4Q4xNAO03
Specifications
| HT Part Number | QDD-400G-4Q4xNAO |
|---|---|
| Manufacturer | HT |
| Form Factor | QSFP-DD to 4x QSFP28 |
| Max. Data Rate | 400Gbps |
| Cable Length Options Covered | 3m (10ft) |
| Cable Type | Breakout AOC |
| Wavelength | 850nm |
| Minimum Bend Radius | 30mm |
| Transmitter Type | VCSEL |
| Receiver Type | PIN |
| Max. Power Consumption | 10W (QSFP-DD End)5.5W (QSFP28 Per End) |
| Jacket Material | OFNP |
| CDR (Clock and Data Recovery) | TX & RX Built-in CDR |
| Modulation Format | QSFP-DD-8x 50G-PAM4QSFP28-4x 25G-NRZ |
| DDM/DOM | Supported |
| Commercial TemperatureRange | 0 to 70°C (32 to 158°F) |
| Protocols | QSFP-DD MSA, SFF-8661, IEEE802.3bs-400GAUI-8, IEEE802.3bm-CAUI-4, CMIS 4.0, SFF-8636 |
Applications and Deployment
An AOC removes the separate module-and-fiber interfaces from a high-speed connection. Both optical ends remain attached to the cable, simplifying polarity control and connector handling. Host identification, wavelength plan, aggregate rate and any breakout configuration must still agree across the link. For this series, the listed interface is QSFP-DD to 4x QSFP28 and the aggregate rate is 400G.
Cisco 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. 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.
Cable Construction and Routing
For this assembly, the jacket material is OFNP; the minimum bend radius is 30mm; the power consumption is 10W (QSFP-DD End)5.5W (QSFP28 Per End). These parameters belong in the installation review rather than being treated as catalogue trivia. Route the cable through its intended managers without tension, avoid pressure close to the connector boots and leave enough space to operate the latches. Any service loop must respect the stated bend limit.
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 series, keep the interface rate, AOC construction and length-specific OEM reference together throughout that review.
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. 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-4Q4xNAO 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.
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. Both connector ends are inspected as part of the complete assembly, and protective packing is selected to avoid tight bends during transport and storage.
Frequently Asked Questions
Is this an original Cisco cable?
No. It is an HT-manufactured compatible cable for equipment that specifies QDD-400G-4Q4xNAO, not an original Cisco-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.
Does this AOC cable require separate modules at each end?
No. The connector ends and cable form one complete direct-attach assembly. The ends are not detachable standalone transceivers, and the complete product is tested together.
What information helps confirm compatibility?
Provide the equipment manufacturer and model, port type, hardware revision and software release, together with the required OEM reference, length and quantity. Breakout projects should also identify the intended lane configuration.
10/100BASE-T SFP