DAC cable CBO QSFP28-DAC-3M 3 m passive QSFP28 direct-attach copper

The CBO QSFP28-DAC-3M is a 3 meter passive direct-attach copper (DAC) cable with QSFP28 connectors, engineered for short-reach 100GbE links. It connects devices with QSFP28 ports—such as switches, routers and servers—without separate transceivers, providing a straightforward physical interconnect for data center topologies, aggregation and cross-connects. The cable is intended for installations where low latency, minimal power consumption and cost-effective cabling are priorities.

Advantages

This passive QSFP28 DAC cable offers low latency and reduced power usage compared with optical transceiver-based links because no active electronics are required in the inline cable. Its fixed 3 m length simplifies inventory and deployment for standard rack or short row connections. The QSFP28 connectors ensure compatibility with equipment supporting 100GbE over QSFP28 ports and enable a compact, high-density cabling approach in racks and patch panels.

Suitable for

• Short-reach 100 Gigabit Ethernet connections between switches in the same rack or adjacent racks
• Direct server-to-switch or server-to-server links where QSFP28 ports are available
• Data center aggregation, spine-leaf architectures and Top-of-Rack cross-connects

Key specifications

• Connector type: QSFP28 to QSFP28
• Cable type: Passive direct-attach copper (DAC)
• Length: 3 meters
• Nominal data rate: Supports 100 Gigabit Ethernet (100GbE)
• Latency: Low latency suitable for high-performance switching environments
• Power: Passive design with negligible inline power consumption
• Form factor: Compact, high-density QSFP28 footprint for rack installations

How to use

Insert each QSFP28 connector into the corresponding QSFP28 port on the devices to be linked, ensuring the connector latch engages. Use the 3 m length to route the cable between devices in the same rack or adjacent racks, avoiding sharp bends and excessive strain on the connector. After physical connection, verify link status on both devices and configure the ports for 100GbE operation as required by your network equipment. If hot-pluggable support is available, connect or disconnect with devices powered on according to the equipment vendor’s guidance.

Usage recommendations

For reliable operation, maintain bend radius and strain-relief best practices, keep the cable away from high-interference power sources, and verify compatibility with the equipment vendor’s QSFP28 port specifications. Use this passive DAC for short distances within racks or across adjacent racks; for longer runs or where active signal conditioning is required, consider optical transceivers and fibre cabling.