DAC cable BlueOptics DAC-Q28-100G-50CM-BL 0.5m QSFP28 Male/Male

The BlueOptics DAC-Q28-100G-50CM-BL is a 0.5 m direct attach cable (DAC) with QSFP28 male connectors on both ends, designed for short-reach, high-speed interconnects in data centers and server racks. This passive twinax copper cable supports 100GBase-CR4 electrical signaling over 0.5 meters and is suitable for linking switches, routers and storage hardware that accept QSFP28 100G DACs. The cable uses 30 AWG conductors and follows MSA-compliant QSFP28 form-factor specifications to ensure physical compatibility with standard 100G ports.

Advantages

The DAC-Q28-100G-50CM-BL provides low-latency, low-power connectivity for short-distance links, with passive design that removes the need for active transceivers and reduces power consumption. Manufactured to MSA guidelines and assembled from industry-standard components, the cable offers stable electrical performance for Ethernet, FCoE, Fibre Channel and InfiniBand applications at 100 Gbps on 0.5 m runs. Its compact 0.5 m length is optimized for in-rack and adjacent-rack connections, minimizing cable clutter and insertion loss compared with longer passive copper options.

Suitable for

• In-rack connections between 100G QSFP28 ports (switch-to-switch, switch-to-server)
• Adjacent-rack interconnects in network and compute cabinets
• High-throughput fabric links for storage, Ethernet and FCoE deployments
• Short-reach InfiniBand or proprietary 100G links where QSFP28 DACs are supported

Key specifications

• Length: 0.5 meter (0.5 m)
• Connector type: QSFP28 Male to QSFP28 Male
• Data rate: up to 100 Gbps (100GBase-CR4 compatible)
• Cable type: passive twinax copper (DAC)
• Wire gauge: 30 AWG
• Form factor compliance: QSFP28 / MSA-compatible
• Typical applications: Ethernet, FCoE, Fibre Channel, InfiniBand

How to use

Insert each QSFP28 connector into the corresponding QSFP28 port on the devices to be connected, ensuring proper orientation and fully seated connectors. Verify that the host hardware and firmware support passive 100G DACs and the 100GBase-CR4 electrical interface. After physical installation, check link status on both devices and confirm negotiated speed and protocol. No additional power or external transceivers are required for passive operation, but equipment configuration may be needed to enable specific protocols or link aggregation.

Recommendations

Use this 0.5 m QSFP28 DAC for short-distance in-rack or adjacent-rack links where low latency and low power consumption are priorities. Confirm compatibility with your switch, router or storage platform and update device firmware if required. Avoid sharp bends and excessive strain on the cable; maintain recommended bend radius and secure routing to prevent mechanical stress. For deployments beyond short reaches, consider optical transceivers or active copper solutions.