InfiniBand/fibre optic cable BlueOptics QDD-400G-DAC-1M-BL 1m QSFP-DD Male/Male

The BlueOptics QDD-400G-DAC-1M-BL is a 1 meter QSFP-DD to QSFP-DD direct attach cable (DAC) designed for 400G data transmission in InfiniBand and short-reach fibre optic/copper twinax environments. This male-to-male cable implements 400GBase-CR4 signalling over a 26 AWG twinax conductor and is MSA-compliant for use in racks and adjacent-rack connections within data centers and high-performance computing installations. The cable is intended for linking switches, routers, storage systems and other hardware platforms that support QSFP-DD 400G direct attach connections.

Advantages

The cable provides low-latency, high-bandwidth connectivity suitable for demanding network environments, while its passive twinax design keeps power consumption minimal. Compliance with MSA interconnect standards and use of quality components ensures stable transmission and broad hardware compatibility. The 1 m length is optimized for short connections inside racks or between adjacent racks, offering straightforward installation and low failure risk due to its simple passive construction.

Suitable for

• High-performance computing clusters and InfiniBand fabrics
• Data center rack-to-rack links and top-of-rack connections
• Switch-to-switch, switch-to-router and switch-to-storage short-reach links
• Environments requiring 400GBase-CR4 electrical connectivity over 1 m

Key specifications

• Connector type: QSFP-DD male to QSFP-DD male
• Nominal data rate: up to 400 Gbit/s
• Length: 1 metre (approx.)
• Cable type: passive twinax (copper) with 26 AWG conductors
• Standards: MSA-compliant QSFP-DD form factor and 400GBase-CR4 signalling
• Typical use: short-reach, within-rack or adjacent-rack connections

How to use

Install the BlueOptics QSFP-DD DAC by inserting each QSFP-DD plug into the corresponding QSFP-DD port on your hardware until it latches. Ensure that both devices support passive 400G DAC connections and the 400GBase-CR4 electrical protocol. Route the cable to avoid sharp bends and mechanical strain, and verify link status via the attached devices' management interfaces. For best results, perform a link test after installation and confirm negotiated speed and lane configuration in the equipment diagnostics.

Recommendations

Use this 1 m passive QSFP-DD DAC for short-distance, high-throughput links inside racks or between adjacent racks. Confirm compatibility with your switch, router or storage vendor and their firmware requirements before deployment. Avoid exceeding the recommended bend radius and keep the cable clear of hot airflow paths to maintain long-term signal integrity.