DAC cable CBO QSFP28-DAC-0.5M 0.5 m passive copper QSFP28

The BlueOptics CBO QSFP28-DAC-0.5M is a 0.5 m passive copper direct-attach cable with QSFP28 interfaces, engineered for short-range 100Gbps server, switch and storage interconnects. The cable enables rack-level connections between compatible QSFP28 ports without the need for transceivers, providing a compact, low-latency alternative to optical links. Its passive design consumes no additional power for signal conversion and supports standard 100 Gigabit Ethernet links over a short 0.5 metre distance.

Advantages

This passive QSFP28 DAC cable provides cost-effective 100Gbps connectivity with minimal latency and low power consumption compared with active optics. The fixed 0.5 m length allows neat rackside routing and reduced signal attenuation for close-proximity ports. Compatibility with QSFP28 ports simplifies installation and avoids separate transceivers, reducing component count and maintenance points.

Suitable for

• Top-of-rack and adjacent-rack interconnections in data centers
• High-speed links between servers and switches supporting QSFP28
• Short-range storage array connections and fabric links
• Low-latency cluster and compute node interconnects

Key specifications

• Connector type: QSFP28 to QSFP28 passive copper
• Length: 0.5 metre
• Data rate: Designed for 100 Gbps links
• Cable type: Direct-attach copper (passive)
• Typical use: Short-reach, rack-level interconnects
• Latency: Low, suitable for latency-sensitive applications

How to use

Install the cable by plugging each QSFP28 end into the corresponding QSFP28 port on your compatible network device. Ensure devices are powered off or meet hot-plug guidelines from the device manufacturer before insertion if required. Verify link status after connection through the host or switch management interface and observe standard diagnostics to confirm 100Gbps link establishment. The cable requires no additional adapters or transceivers.

Recommendations

Use the 0.5 m passive QSFP28 DAC for short-distance connections within the same rack or adjacent racks where 100Gbps throughput and low latency are required. Avoid exceeding the specified mechanical bend radius and protect the connectors from contamination to maintain link quality. For longer runs or where optical isolation is required, consider optical transceivers and fiber cables instead.