BlueOptics QSFP-4SFP25G-CU5M-BL InfiniBand fibre optic cable 5 m QSFP28 4xSFP28 Male Male

The BlueOptics QSFP-4SFP25G-CU5M-BL is a 5 m direct-attach twinax cable with a QSFP28 connector on one end and four SFP28 connectors on the other. Designed for short-reach, high-speed interconnects, this passive 100G to 4x25G breakout cable supports InfiniBand and Ethernet signaling for use in racks and between adjacent racks in data center and networking environments. The cable implements a 26 AWG twinax conductor and follows MSA-defined electrical and mechanical interfaces for QSFP28 breakout DACs.

Advantages

This passive DAC provides low latency and low power consumption due to its twinax copper design and lack of active electronics. It is manufactured to industry MSA specifications for QSFP28-to-4xSFP28 breakout applications, enabling interoperability with platforms that support QSFP-4SFP25G-style breakout cables. The cable uses robust components and assembly practices intended to deliver long service life and stable electrical characteristics for short-distance, high-bandwidth links.

Suitable for

• High-density switch-to-switch or switch-to-server connections inside racks
• Breakout of a 100G QSFP28 port into four 25G SFP28 ports
• InfiniBand, Ethernet (100GBase-CR4 / 4x25GBASE-CR) and similar short-reach protocols
• Adjacent-rack interconnects where passive DAC is supported by the hardware

Key specifications

• Cable type: passive twinax copper (direct attach cable)
• Length: 5 meters
• Connectors: 1× QSFP28 (male) to 4× SFP28 (male)
• Bandwidth: up to 100 Gbit/s aggregate (4×25 Gbit/s lanes)
• Wire gauge: 26 AWG
• Compliance: MSA-compliant QSFP28 breakout DAC electrical/mechanical profile
• Typical applications: short-reach data center interconnects, breakout links

How to use

Confirm that the target devices support passive QSFP28-to-4xSFP28 breakout cables and that the intended ports are enabled for the corresponding protocol (100GBase-CR4 / 4x25GBASE-CR or InfiniBand). Power down or follow the manufacturer's hot-swap guidance for your hardware if required. Insert the QSFP28 plug into the source QSFP port and insert each SFP28 plug into the destination SFP ports until the latch engages. Verify link status and correct lane mapping in your switch or host firmware and configure interfaces as needed for the chosen protocol.

Recommendations

Use this 5 m passive DAC for short-distance, high-bandwidth links inside racks or between adjacent racks where passive twinax is supported; avoid using it for longer runs or in installs that require optical transceivers. Ensure firmware and hardware compatibility with QSFP28 breakout cables and test links after installation to confirm proper operation.