InfiniBand/fibre optic cable BlueOptics AT-QSFP-4SFP10G-3CU-BL 3 m Male/Male

The BlueOptics AT-QSFP-4SFP10G-3CU-BL is a 3 m InfiniBand/fibre optic direct-attach cable with a QSFP connector on one end and four SFP+ interfaces on the other, designed for high-speed rack and adjacent-rack interconnects. It implements a passive twinax copper design suitable for short-distance 40GBase-CR4 / 4x10GBase-CR applications and is MSA-compliant for interoperability with hardware that supports QSFP-to-4xSFP+ breakouts. The cable is intended for use in data center switches, routers and storage systems where reliable low-latency, high-bandwidth links are required.

Advantages

This 3 m QSFP-to-4xSFP+ cable provides up to 40 Gbit/s aggregate bandwidth using a passive twinax copper construction, which results in low power consumption and minimal latency compared with active or optical alternatives for the same short-reach links. MSA compliance ensures mechanical and electrical interoperability with compatible network equipment. The cable uses industry-grade components and production processes aimed at long operational lifetime and consistent performance for data center deployments.

Suitable for

• QSFP-to-SFP+ breakout connections between switches and top-of-rack devices
• High-density rack interconnects and adjacent-rack links up to 3 m
• 40G Ethernet, FCoE, and InfiniBand short-reach connections where passive DAC is supported
• Upgrading port density in network, server and storage enclosures

Key specifications

• Cable length: 3 m
• Connector type: QSFP (one end) to 4 × SFP+ (other end)
• Topology: passive twinax copper (breakout DAC)
• Supported data rates: up to 40 Gbit/s aggregate (4 × 10 Gbit/s lanes)
• Wire gauge: 30 AWG
• Standards compliance: MSA (QSFP breakout DAC), suitable for 40GBase-CR4 / 4x10GBase-CR
• Typical applications: Ethernet, FCoE, Fibre Channel and InfiniBand short-reach links

How to use

Install the cable by inserting the QSFP connector into the QSFP port of the originating device and the four SFP+ plugs into the destination device ports, ensuring correct orientation and secure seating. Use this passive DAC only for short-distance connections (up to 3 m) and verify that both devices explicitly support passive QSFP-to-4×SFP+ breakout cables. Confirm link negotiation and port configuration on both devices after physical installation; when required, adjust switch or host settings to enable 40G/10G lane breakout modes.

Recommendations

For reliable operation, avoid sharp bends and excessive tensile stress on the cable, maintain slack to prevent strain on connectors, and route the cable away from sources of electromagnetic interference. Check hardware compatibility and firmware requirements before deployment and test each link in the target environment. If longer reaches or optical isolation are needed, choose appropriate active DAC or optical transceivers and fibre cables instead of a passive twinax solution.