BlueOptics QDD-2X200G-2M-BL InfiniBand/fibre optic cable QSFP-DD 2xQSFP56 2m Male/Male

The BlueOptics QDD-2X200G-2M-BL is a 2‑meter direct attach cable (DAC) featuring a QSFP-DD connector on one end and two QSFP56 connectors on the other. It supports 400GBase-CR8 and 2x200GBase-CR4 electrical transmission over twinax copper with 26 AWG conductors and is MSA-compliant. Designed for short-range high‑speed links in racks and between adjacent racks, this cable provides low latency and reliable signal integrity for InfiniBand, Ethernet and storage interconnects.

Advantages

The cable delivers up to 400 Gbit/s aggregate throughput using a QSFP-DD to 2xQSFP56 pinout while remaining passive, which reduces power consumption and latency compared with active solutions. Construction uses industry-standard twinax materials and compliant mechanical interfaces to ensure compatibility with hardware platforms that support the corresponding QDD/2xQSFP56 wiring. The 2 m length is suitable for typical rack-to-rack or intra-rack connections and the 26 AWG conductor provides a balance of flexibility and signal performance.

Suitable for

• High-speed switch-to-switch connections within the same rack or adjacent racks
• Server or storage system uplinks requiring 400G or 2x200G electrical links
• InfiniBand fabrics and Ethernet backplane interconnects in data centers

Key specifications

• Connector type: QSFP-DD (one end) to 2×QSFP56 (other end)
• Length: 2 meters
• Transmission: Passive twinax copper, 400GBase-CR8 / 2×200GBase-CR4
• Conductor gauge: 26 AWG
• Compliance: MSA-compliant mechanical and electrical pinout
• Applications supported: Ethernet, InfiniBand, FCoE and Fibre Channel up to 400 Gbit/s over specified distance

How to use

Install the cable by inserting the QSFP-DD plug into a compatible QSFP-DD port and the two QSFP56 plugs into corresponding QSFP56 ports. Ensure both devices support passive DAC connections and the intended 400GBase-CR8 or 2×200GBase-CR4 transmission mode. Handle connectors by their housing, avoid excessive bending near the connector boot, and verify link status LEDs on connected equipment after insertion. No external power or configuration is required for the cable itself; configuration is performed on the connected hardware as needed for link negotiation and protocol settings.

Recommendations

Use this passive QSFP-DD to 2×QSFP56 twinax cable for short-range electrical interconnects where low latency and low power consumption are priorities. Confirm vendor compatibility with your network equipment and firmware, route the cable to avoid sharp bends and mechanical strain, and keep the operating environment within the equipment manufacturer’s temperature and humidity limits to maintain long service life.