Direct Attach Copper (DAC) Cable CBO QSFP28-DAC-5M 5 m, QSFP28 to QSFP28

The BlueOptics Direct Attach Copper (DAC) Cable CBO QSFP28-DAC-5M is a 5-metre copper twinax assembly with QSFP28 connectors on both ends, designed for short-range high-speed interconnects. This cable is compatible with Mikrotik equipment and intended for linking QSFP28 ports on switches, routers and servers within the same rack or in adjacent cabinets. The direct-attach design provides a fixed, low-latency electrical connection without the need for separate transceivers, making it a practical choice for dense data centre and enterprise networking environments.

Advantages

The DAC cable delivers a cost-effective alternative to optical transceivers and fiber for short distances, offering low latency and high signal integrity over a 5 m reach. With QSFP28 connectors at both ends the assembly simplifies port-to-port connections between compatible QSFP28 interfaces and reduces power consumption compared to active optical or transceiver-based links. The cable's pre-terminated twinax construction ensures straightforward installation and predictable performance in rack-to-rack or within-rack deployments.

Suitable for

• Interconnecting QSFP28 ports on switches and routers within the same rack
• Connecting servers with QSFP28 network interfaces to top-of-rack switches
• Short-reach links between adjacent server or network cabinets
• High-density data centre environments requiring low-latency connections

Key specifications

• Length: 5 metres
• Connector type: QSFP28 to QSFP28
• Media: Direct attach copper (twinax)
• Application: Short-range, high-speed interconnects (within rack / adjacent racks)
• Compatibility: Designed for use with equipment that supports QSFP28 electrical DAC connections, including Mikrotik

How to use

Install the cable by inserting each QSFP28 connector into the corresponding QSFP28 port until the latch engages. Ensure both connected devices are powered down or that hot-plugging is supported by the equipment to avoid link negotiation issues, then power on and verify link status through device LEDs or management interfaces. For optimal signal integrity, route the cable without sharp bends and avoid kinking or excessive twisting. Use appropriate cable management to maintain clear airflow and serviceability within the rack.

Recommendations

Use the 5 m DAC cable for short, direct connections where cost, power efficiency and low latency are priorities. Verify QSFP28 DAC support and firmware compatibility on both endpoints before deployment, and keep the cable away from high electromagnetic interference sources. Regularly inspect connectors for debris or damage and replace the cable if physical wear is observed.