BlueLAN 400GBASE-CR8 QSFP-DD to 4x100GBASE-CR QSFP56 Breakout Direct Attach Cable, 1m, AWG26, Passive (BL2907401X1M26-BL)

Data center engineers deploying high-density 400G switches often need to connect to multiple 100G ports without adding optical transceivers. This BlueLAN breakout DAC cable plugs directly into a QSFP-DD port and splits into four QSFP56 ends, enabling a clean 400G-to-4x100G link over a single meter. Its passive twinax design consumes no power and adds near-zero latency, making it a practical choice for top-of-rack aggregation and spine-leaf architectures.

Key specifications

• Connector A: QSFP-DD (400GBASE-CR8)
• Connector B: 4x QSFP56 (100GBASE-CR each)
• Aggregate data rate: 400 Gbps (4x 100 Gbps)
• Cable length: 1 meter
• Wire gauge: AWG26
• Cable type: Passive Direct Attach Copper (DAC) breakout
• Electrical interface: Copper twinax
• Compliance: IEEE 802.3cd, SFF-8636, SFF-8665
• Hot-pluggable: Yes

Why choose it

Passive DAC cables are the most cost-effective way to bridge short distances inside a rack or between adjacent racks. This breakout cable eliminates the need for separate optics and fiber patch cords, reducing both capital expense and points of failure. The QSFP-DD connector is backward-compatible with QSFP28 cages, giving you flexibility in mixed-generation environments. With AWG26 conductors, the cable balances flexibility and signal integrity for 1-meter runs at full 400G speed.

Ideal use cases

• Connecting a 400G QSFP-DD switch port to four 100G QSFP56 server or switch ports
• High-performance computing clusters requiring dense, low-latency interconnects
• Enterprise data centers upgrading to 400G aggregation while retaining 100G access devices
• Lab and test environments validating 400G-to-100G breakout configurations

Good to know

The cable is fully passive, so no driver or firmware is needed—just plug and play. Because it draws no power, it contributes to lower overall energy consumption in high-density racks. The 1-meter length is ideal for intra-rack connections; for longer distances, consider an active optical cable (AOC). The breakout ends are individually labeled for easy identification during installation.