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Axiom QDD-400-CU2. 5M-AX 400GBASE-CU QSFP-DD Passive DAC Cable - 2. 5m - 8. 2 ft Twinaxial - Cisco Compatible
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Product Features
Technical Overview
This QSFP-DD passive DAC cable operates at 400 Gbit/s data transfer rates using twinaxial copper cable technology. The passive design means it requires no external power source or signal processing electronics, relying instead on the host equipment's electrical signaling capabilities. This results in lower power consumption and reduced heat generation compared to active optical solutions.
The cable utilizes QSFP-DD (Quad Small Form-factor Pluggable Double Density) connectors on both ends, which support eight lanes of 50 Gb/s electrical signaling to achieve the total 400 Gb/s bandwidth. This connector format is backward compatible with QSFP+ and QSFP28 ports through appropriate adapters, though optimal performance requires native QSFP-DD interfaces.
Key Product Advantages
This DAC cable provides several distinct advantages for network infrastructure deployments where high-speed, short-reach connections are required between compatible networking equipment.
Cost-Effective 400GbE Connectivity
Delivers full 400 Gbit/s performance without the expense of separate optical transceivers and fiber cabling, reducing total cost of ownership for short-distance links.
- Eliminates transceiver costs
- No fiber patch panels required
- Lower power consumption than active solutions
Simplified Deployment & Management
The plug-and-play passive design requires no configuration or management, reducing installation time and complexity compared to optical alternatives.
- No DDM/DOM monitoring needed
- Immediate link establishment
- Reduced troubleshooting overhead
Reliable Physical Connection
Twinaxial copper construction provides durable, EMI-resistant connectivity that's less fragile than fiber optics for intra-rack and adjacent equipment connections.
- Superior mechanical durability
- Resistant to bending stress
- Stable electrical performance
Deployment / Use Cases
This 400GBASE-CU QSFP-DD passive DAC cable is designed for specific high-speed networking scenarios where short-distance, high-bandwidth connections are essential for modern data center and enterprise network performance.
Primary deployment scenarios include connecting top-of-rack switches to aggregation switches within the same rack or adjacent racks, establishing spine-leaf connections in fabric architectures, and linking high-performance servers to network switches in HPC and storage environments. The 2.5-meter length is particularly well-suited for these common intra-rack and inter-rack applications where distance requirements typically fall under 3 meters.
Data Center Spine-Leaf Architecture
Ideal for establishing 400GbE connections between spine and leaf switches in modern data center fabrics, providing the high bandwidth needed for East-West traffic flows without the complexity of optical infrastructure.
High-Density Switch Interconnection
Enables cost-effective stacking and interconnection of QSFP-DD equipped switches in high-density rack deployments, maximizing port utilization while minimizing cabling complexity and costs.
Highlights
- 400 Gbit/s data transfer rate for high-bandwidth applications
- QSFP-DD connectors on both ends for 400GbE connectivity
- 2.5-meter (8.2-foot) twinaxial copper cable length
- Passive design requires no external power or management
- Cisco compatible for use with Cisco networking equipment
- Supports switches, routers, and network devices
- Lifetime warranty for long-term reliability assurance
- Black color for consistent rack aesthetics
Specifications
| Specifications | |
|---|---|
| Manufacturer | Axiom Memory Solutions |
| Manufacturer Part Number | QDD-400-CU2.5M-AX |
| Brand Name | Axiom |
| Product Name | 400GBASE-CU QSFP-DD Passive DAC Cable Cisco Compatible 2.5m |
| Product Type | Network Cable |
| Technical Information | |
| Cable Type | Twinaxial |
| Cable Length | 8.2 ft (2.50 m) |
| Connector Type on First End | QSFP-DD Network |
| Connector on First End Details | 1 x QSFP-DD Network |
| Connector Type on Second End | QSFP-DD Network |
| Connector on Second End Details | 1 x QSFP-DD Network |
| Device Supported | Switch,Router,Network Device |
| Data Transfer Rate | 400 Gbit/s |
| Features | Passive |
| Physical Characteristics | |
| Product Color | Black |
| Warranty | |
| Limited Warranty | Lifetime |
FAQ
What is the maximum distance supported by this DAC cable?
This passive DAC cable is designed for short-reach applications up to 3 meters, with this specific model providing 2.5 meters (8.2 feet) of reach. Passive copper DAC cables are typically recommended for distances under 5 meters, as signal integrity degrades beyond this range without active signal conditioning. For longer distances, active optical cables or separate transceivers with fiber optic cabling would be more appropriate.
Is this cable compatible with non-Cisco networking equipment?
While marketed as Cisco compatible, QSFP-DD DAC cables generally work with any networking equipment that supports the QSFP-DD form factor and 400GBASE-CU electrical specification. However, compatibility should be verified with the specific equipment manufacturer, as some vendors implement proprietary coding or signaling requirements. The passive design typically offers broader compatibility than vendor-coded active optical solutions.
What does 'passive' mean for a DAC cable?
Passive means the cable contains no active electronics for signal processing, retiming, or amplification. It relies entirely on the host equipment's electrical drivers to transmit signals through the copper conductors. This results in lower power consumption, reduced heat generation, and typically lower cost compared to active DAC cables, but with more limited reach capabilities (usually under 5 meters for 400GbE applications).
Can this cable be used for 100GbE or 200GbE connections?
QSFP-DD ports and cables can support multiple data rates through negotiation with the connected equipment. While this cable is designed for 400GbE operation, it may support lower speeds like 200GbE or 100GbE if the connected equipment negotiates accordingly. However, optimal performance is achieved at the native 400 Gbit/s rating, and compatibility at lower speeds should be verified with the specific equipment being connected.
| Qty | Price | Available |
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