BlueOptics BlueLAN passive QSFP112 Direct Attach Cable 400GBASE Ethernet / InfiniBand, 2 m

BlueOptics BlueLAN passive QSFP112 Direct Attach Cable 400GBASE Ethernet / InfiniBand, 2 m is a factory-terminated copper DAC designed to provide a fixed, high-bandwidth connection between 400GBASE-capable network devices. The 2 meter length is intended for short-reach interconnects in data centers and high-performance computing racks where direct attach cabling simplifies infrastructure and avoids the need for active optical transceivers. This cable supports QSFP112 form-factor ports and is suitable for use with switches, routers and network interface cards that accept passive 400G direct attach links.

Advantages

The passive QSFP112 DAC offers predictable latency and stable electrical performance without consuming power for active components, which can lower device power draw. A factory-terminated copper assembly reduces deployment time and potential connector mismatch. The 2 m length balances reach and signal integrity for short interconnects while maintaining the full 400G data rate for Ethernet and InfiniBand applications.

Suitable for

• Short-reach interconnects within server racks and between adjacent racks
• 400GBASE Ethernet uplinks and spine/leaf connections in data centers
• High-performance computing clusters using InfiniBand or Ethernet at 400 Gbit/s
• Direct-attach connections between switches, routers and NICs with QSFP112 ports

When it may not be suitable

This passive copper direct attach cable is not suitable for longer-distance links that require optical transceivers or active cabling solutions; its performance is limited to short-reach topologies. It may also be incompatible with devices that do not support QSFP112 passive DACs or that require vendor-specific transceiver authentication.

Key specifications

• Connector type: QSFP112 to QSFP112 passive copper assemblies
• Supported data rate: 400 Gbit/s
• Media: Twinax copper, passive
• Length: 2 meters
• Applications: 400GBASE Ethernet, InfiniBand
• Typical use: Short-reach rack and adjacent-rack connections

How to use

Insert each QSFP112 connector into the corresponding port on the two devices until the retention latch engages; ensure both ports are rated for 400G passive DACs. No additional configuration is required on the cable itself, but verify device firmware and port settings to enable 400G operation. Route the cable to avoid sharp bends and maintain recommended bend radius for twinax copper assemblies. For best results, install with devices powered down or after confirming the host ports support hot-plugging according to the equipment vendor guidance.

What to consider before purchase

• Confirm both endpoints have QSFP112 ports that accept passive 400G direct attach cables
• Verify the 2 m length matches rack layout and does not require longer reach
• Check device compatibility notes for any vendor locking or transceiver validation
• Ensure your environment and airflow requirements are compatible with copper DAC routing

Usage recommendations

Use the BlueOptics 2 m passive QSFP112 DAC for short, direct connections where consistent 400G performance and low power consumption are priorities. Maintain manufacturer-recommended bend radius, avoid repeated unplugging that may stress contacts, and verify device firmware and port settings to ensure full 400G operation.