CBO InfiniBand Cable CAB-Q28-S28-3M-BL QSFP28 to 4×SFP28, length 3 m, blue

The CBO InfiniBand Cable CAB-Q28-S28-3M-BL is a passive QSFP28-to-4×SFP28 breakout cable with a 3 meter blue jacket designed for short-reach, high-bandwidth connections. It converts a single QSFP28 port into four independent SFP28 links, enabling direct interconnection between servers, switches and storage devices that support QSFP28 and SFP28 interfaces. The cable is intended for environments where compact, reliable copper cabling is needed for port consolidation, test setups and short-distance interconnects.

Advantages

This passive breakout cable offers straightforward installation with no external power or active components required, reducing complexity in rack deployments. The 3 m length provides flexibility within racks and between adjacent equipment; the blue jacket aids visual identification in cable runs. Because it uses standardized QSFP28 and SFP28 connectors, it supports native electrical pinouts for direct port mapping and simplifies migration strategies from 25/100GbE and InfiniBand QSFP-based links to multiple SFP28 endpoints.

Suitable for

Key specifications

How to use

Ensure both the QSFP28 host port and the target SFP28 ports support passive breakout connections and compatible electrical pinouts. With equipment powered off or in maintenance mode, insert the QSFP28 end into the QSFP28 port and connect each SFP28 plug to the desired SFP28 ports on the remote device. Power the equipment and verify link status and negotiated speeds in the host and remote interfaces. For migration scenarios, map VLANs or port configurations as needed so each SFP28 link functions as an independent 25Gb/s channel.

Recommendations

Use this cable for short-reach, in-rack interconnects and testing. Avoid running the cable over long distances; passive copper breakout cables are intended for short links and may not meet signal integrity requirements for extended runs. Keep bends gentle and maintain bend radius recommendations from equipment vendors to preserve connector reliability and signal performance.