Copper DAC cable CBO QSFP28 to 4×SFP28, passive, 3 m

The Copper DAC cable CBO QSFP28 to 4×SFP28, passive, 3 m is a fixed-length direct attach copper assembly designed to provide a cost-efficient, low-latency connection between a QSFP28 port and four SFP28 ports. Intended for short-reach interconnects in data centres, network racks and server rooms, this passive 3 m cable eliminates the need for separate optical transceivers while supporting high-density breakout and link aggregation setups. The construction and connector arrangement make it suitable for rack-mounted switches, servers and storage systems that require reliable 100 Gbps-to-4×25 Gbps breakout links.

Advantages

This passive copper DAC offers predictable electrical performance with minimal latency and low power consumption compared with active or optical solutions. The integrated QSFP28 and four SFP28 connectors simplify breakout installations and reduce component count in high-density environments. The fixed 3 m length supports tidy cable management in typical rack depths and helps avoid excess slack. As a passive assembly, it provides a cost-effective alternative for short-distance 100G-to-4×25G connections without optical modules or separate transceivers.

Suitable for

• Short-reach breakout connections between a QSFP28 port and multiple SFP28 ports in data centres
• High-density switch-to-server or switch-to-storage interconnects within the same rack or adjacent racks
• Link aggregation and breakout configurations that require 100 Gbps to be split into 4×25 Gbps channels
• Environments where low latency and low power consumption are priorities

Key specifications

• Cable type: passive direct attach copper (DAC)
• Connector configuration: QSFP28 (one end) to 4 × SFP28 (other end)
• Length: 3 m (fixed)
• Data rate support: 100 Gbps aggregated to 4 × 25 Gbps
• Typical application: short-reach rack and cabinet interconnects
• Physical form factor: fixed-cable breakout assembly for high-density deployment

How to use

Insert the QSFP28 connector into the 100G QSFP28 port of the switch, router or host interface, and insert each SFP28 connector into the corresponding 25G SFP28 ports on the receiving device. Ensure devices are powered down or follow hot-plug procedures specified by the equipment vendor if supported. Route the cable to avoid sharp bends and maintain the recommended bend radius for copper assemblies. Verify link status and speed on both ends after installation and configure switch or host ports for breakout or aggregation as required by your network design.

Recommendations

For optimal performance, use the 3 m passive DAC for intra-rack or adjacent-rack connections only. Avoid extended cable runs and environments with high electromagnetic interference. Confirm compatibility with your hardware vendor’s supported copper DAC list and follow proper handling to prevent connector damage.