DAC cable CBO Q28-4S28-DAC-3M-QL-BL 3 m QSFP28 100 Gbit/s

Direct attach copper (DAC) cable CBO Q28-4S28-DAC-3M-QL-BL is a 3 m passive QSFP28 interconnect that supports 100 Gbit/s data rates. The BlueOptics cable is intended for short-reach connections between switches, servers and network appliances where a low-latency, cost-effective and energy-efficient electrical link is required without separate optical transceivers. Its fixed 3 m length and QSFP28 connector format make it suitable for rack-to-rack and within-rack high-speed links in data center environments.

Advantages

The DAC cable offers a direct electrical connection that reduces power consumption compared with optical transceiver-based links and eliminates the need for separate SFP/QSFP modules. Passive construction minimizes latency and complexity while providing a secure physical link. The 100 Gbit/s QSFP28 interface ensures compatibility with equipment supporting QSFP28 ports and short-reach copper connections, and the fixed 3 m length simplifies cable management for defined rack layouts.

Suitable for

• Short-reach switch-to-switch connections in data centers
• Server-to-switch high-speed uplinks within racks
• Rack-to-rack interconnects over a 3 m span
• Network appliances requiring QSFP28 100 Gbit/s electrical links

Key specifications

• Connector type: QSFP28
• Data rate: 100 Gbit/s
• Length: 3 m (fixed)
• Cable type: Direct attach copper (passive DAC)
• Application: Short-reach, rack-to-rack and within-rack interconnects

How to use

Insert each QSFP28 plug into the corresponding QSFP28 port on the network devices until the latch engages; ensure ports are powered down or follow hot-plug procedures recommended by the device manufacturer. Verify link status through device management interfaces after connection. Use the fixed 3 m length to route the cable cleanly along rack rails or cable management pathways to avoid sharp bends and mechanical strain on the connectors.

Recommendations

Use the DAC cable in short-reach scenarios up to 3 m and within equipment compatibility lists that support passive QSFP28 copper assemblies. Avoid excessive bending near the connector ends, keep the cable away from sources of strong electromagnetic interference, and follow chassis vendor guidelines for hot-plugging and port compatibility.