DAC cable CBO QSFP28-DAC-3M passive copper 3 m for QSFP28 ports

CBO QSFP28-DAC-3M is a 3-meter passive copper Direct Attach Cable (DAC) engineered for QSFP28 ports to provide cost-effective, short-reach 100Gbps links. The fixed-length twinax design eliminates the need for separate optical transceivers, offering a low-latency, low-power connection between compatible switches, servers and network appliances in data centre topologies. The cable is intended for direct rack-to-rack or within-rack interconnects where a reliable, high-bandwidth physical link is required.

Advantages

The passive copper construction delivers reduced power consumption compared with active or optical solutions while keeping signal integrity over the specified 3 m range. Because it is a pre-terminated twinax assembly designed for QSFP28 ports, installation is simple and requires no additional modules, which lowers capital and operating costs. The cable supports 100Gbps data rates with minimal latency and predictable electrical performance suitable for short-range interconnects.

Suitable for

• Switch-to-switch connections within the same rack or adjacent racks
• Switch-to-server links for high-throughput applications
• Top-of-rack (ToR) and leaf-spine data centre architectures
• Short-reach, high-bandwidth interconnects in campus or enterprise networks

Key specifications

• Connector type: QSFP28 to QSFP28 passive twinax assembly
• Length: 3 metres
• Data rate: 100 Gbps
• Cable type: Passive copper (twinax)
• Latency: low, suitable for short-range, high-performance links
• Power: passive design, reduced power consumption compared with optical transceivers

How to use

Verify that both endpoints have QSFP28 ports that support passive DAC connections and that the device firmware and port configurations are compatible with 100Gbps operation. Align each QSFP28 connector with the port and insert until the latch engages; no additional transceivers or external power are required. For hot-plug capable equipment, insert or remove the cable while the system is powered according to the host device guidelines. After installation, confirm link status and negotiated speed in the network device management interface.

Recommendations

Use this 3 m passive DAC for short-distance links inside racks or between adjacent racks to minimize latency and power usage. Avoid sharp bends and excessive pulling forces on the cable; maintain the manufacturer’s minimum bend radius and keep the cable clear of heat sources and moving parts. For environments where longer reach or optical isolation is required, consider appropriate active copper or optical transceiver solutions.