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

Passive Direct Attach Copper (DAC) cable CBO QSFP28 to 4× SFP28 passive, 3 m length provides a compact and reliable physical connection for breaking out a single 100Gb/s QSFP28 port into four independent 25Gb/s SFP28 links. Designed for short-reach high-speed interconnects in data centers and server racks, this 3 meter DAC cable offers a low-latency, low-power alternative to active optics while supporting plug-and-play installation with compatible switches, routers and network interface cards.

Advantages

The passive DAC construction ensures minimal signal processing and lower power consumption compared with active transceivers. Its breakout design enables flexible port utilization by converting one QSFP28 lane into four SFP28 ports without additional media converters. The 3 m length is suitable for rack-to-rack or switch-to-server connections within the same equipment bay, and the cable’s passive nature reduces heat generation and operational complexity. Compatibility with standard QSFP28 and SFP28 form factors simplifies installation and replacement.

Suitable for (tasks / use cases)

• 100Gb/s to 4×25Gb/s breakout connections in data centers
• High-density switch-to-server links within racks and cabinets
• Short-reach interconnects in top-of-rack and end-of-row deployments
• Low-latency connections for compute clusters and storage arrays

Key specifications

• Connector type: one QSFP28 plug to four SFP28 plugs
• Function: passive direct attach copper breakout cable
• Data rate: supports 100Gb/s aggregate with 4×25Gb/s lanes
• Length: 3 meters
• Latency: negligible added latency typical for copper DAC links
• Power: passive design with reduced power consumption compared to active optics
• Use environment: designed for short-reach, within-rack or adjacent-rack connections

How to use

Insert the QSFP28 end into the 100Gb/s QSFP28 port on the switch or router and connect the four SFP28 ends to SFP28 ports on target devices such as servers or line cards. Ensure both ends are securely seated and that connected equipment supports DAC passive cable connections and the intended breakout configuration. No additional configurations are required at the physical layer; the connected devices will negotiate link speed on the SFP28 ports according to their capabilities.

Recommendations

Use the cable for short-distance, high-speed links within the same rack or between adjacent racks. Avoid tight bends and maintain recommended bend radius to prevent mechanical stress. Verify compatibility with your hardware vendor’s supported transceiver and DAC lists, and check switch firmware or NIC settings if link negotiation issues occur.