CBO DAC cable QSFP-40G-C0.5M 40Gbps direct-attach copper, QSFP+ to QSFP+, 0.5 m

The CBO DAC cable QSFP-40G-C0.5M is a 40Gbps direct-attach copper (DAC) cable with QSFP+ connectors at both ends and a fixed 0.5 m length. It provides a low-latency, high-bandwidth electrical link for short-reach interconnects in data centers, network switches and server racks. The cable is intended as a plug-and-play alternative to optical transceivers for high-speed links where distances are short and power efficiency is important.

Advantages

This QSFP+ to QSFP+ DAC cable delivers 40Gbps aggregate bandwidth with minimal signal conversion, resulting in reduced power consumption and lower latency compared with equivalent optical solutions. The fixed copper assembly eliminates the need for separate transceivers and fiber patching, simplifying rack cabling and reducing component count. Its short 0.5 m length is optimized for direct interconnects such as switch-to-switch or switch-to-server connections inside a rack or adjacent racks, ensuring a compact and reliable physical connection.

Suitable for

• Short-reach 40Gbps links between switches (spine-leaf and top-of-rack)
• Server uplinks and direct server-to-switch connections
• Switch stacking and intra-rack high-bandwidth connections
• Environments where lower power and minimal latency are required

Key specifications

• Data rate: 40 Gbps aggregate
• Connector type: QSFP+ to QSFP+
• Length: 0.5 m fixed
• Media: Direct-attach copper
• Application: Short-reach electrical interconnects
• Installation: Plug-and-play, no transceivers required

How to use

Install the cable by inserting each QSFP+ connector into the appropriate ports on the network devices until the modules latch. Ensure ports are powered down or follow hot-plug guidelines from the equipment vendor if applicable. After physical installation, verify link status and speed through the host devices or switch management interface. Because the cable is a fixed assembly, no additional configuration is required on the cable itself.

Recommendations

Use this 0.5 m DAC cable for intra-rack or adjacent-rack 40Gbps links where short distance, low latency and power efficiency are priorities. Avoid bending the cable sharply beyond the manufacturer’s recommended radius and ensure connectors are kept free of dust and debris when not in use. When connecting different vendors' equipment, verify compatibility with the devices' QSFP+ port firmware and supported link modes.