DAC cable CBO DAC-QSFP-40G-2M-BL — 2 m QSFP+ direct-attach copper, 40 Gbit/s

Direct-attach copper (DAC) cable CBO DAC-QSFP-40G-2M-BL is a 2 m QSFP+ passive cable engineered for short-reach 40 Gbit/s links. It connects QSFP+ ports directly without optical transceivers, delivering high throughput and low latency for rack-level and server-to-switch topologies. The cable is intended for data centre environments where predictable performance, low power consumption and straightforward deployment are priorities.

Advantages

The QSFP+ passive DAC provides a cost-effective alternative to optical modules by eliminating the need for separate transceivers. With a fixed 2 m length and QSFP+ terminations it ensures stable 40 Gbit/s connectivity and minimal signal conversion overhead. Built for short-distance links, the cable reduces power draw compared with active optical solutions and simplifies inventory management by using a standard copper assembly.

Suitable for

• Top-of-rack switch to switch connections
• Server to switch uplinks within the same rack or adjacent racks
• High-throughput, low-latency data centre links
• Temporary deployment or testbench connections in networking labs

Key specifications

• Connector type: QSFP+ to QSFP+
• Data rate: 40 Gbit/s aggregate throughput
• Length: 2 metres
• Cable type: Direct-attach copper (passive)
• Intended reach: short-reach, rack-level interconnects
• Power: passive design, no external power required

How to use

Install the DAC cable by seating each QSFP+ connector into the corresponding QSFP+ port until the latch engages. Ensure both network devices are powered down or interfaces are administratively disabled during installation if required by your change control procedures. After physical installation, verify link status on both endpoints and confirm 40 Gbit/s negotiation and proper lane mapping in device interfaces.

Recommendations

Use this passive QSFP+ DAC for short, fixed-length connections within racks or between adjacent racks. Avoid tight bends and sharp kinks; maintain the manufacturer-recommended bend radius. For longer runs or where optical isolation is required, consider active optical cables or transceiver-based solutions.