Passive 400GBASE-CR8 to 4×100GBASE-CR QSFP-DD to 4×QSFP56 Direct Attach Breakout Cable BlueOptics 1 m AWG26

Passive 400GBASE-CR8 to 4×100GBASE-CR QSFP-DD to 4×QSFP56 Direct Attach Breakout Cable BlueOptics 1 m AWG26 is a passive copper breakout cable designed to split a single 400G QSFP-DD connection into four independent 100G QSFP56 channels. With a 1 meter length and AWG26 conductor gauge, this cable provides a short-reach physical layer solution for connecting high-density switches, routers and network interface cards that support 400G QSFP-DD and 100G QSFP56 interfaces. The construction and pinout follow the established CR8 to CR breakout mapping to ensure compatibility with devices that accept passive copper breakout assemblies.

Advantages

This passive breakout cable offers a compact and low-latency interconnect option without active electronics, reducing power consumption and eliminating the need for external transceivers. The AWG26 copper conductors provide reliable signal integrity for short-reach links while the single-cable breakout simplifies rack cabling and saves port density. The standardized QSFP-DD to QSFP56 pinout enables straightforward integration into data center aggregation layers, server uplinks and high-density top-of-rack switch deployments.

Suitable for

• Data center aggregation and spine-leaf interconnects
• Server uplinks to top-of-rack or aggregation switches
• High-density switch-to-switch connections in short-reach scenarios
• Lab and test environments for validating QSFP-DD to QSFP56 breakout functionality

Key specifications

• Interface: QSFP-DD (400GBASE-CR8) to 4 × QSFP56 (100GBASE-CR)
• Cable type: Passive direct attach copper breakout
• Length: 1 meter
• Conductor gauge: AWG26
• Reach: short-reach copper connections (rack/row level)
• Color: Blue

How to use

Install the cable by inserting the QSFP-DD end into the 400G port and the four QSFP56 ends into the corresponding 100G ports on the target devices. Ensure that devices support passive breakout cabling and the required port modes (CR8 to 4×CR). Confirm link status and lane mapping in device management interfaces after insertion. There is no separate power or configuration required for the cable itself; any required settings are applied on the connected equipment.

Usage recommendations

Use this passive AWG26 breakout cable for short-distance connections within the same rack or adjacent racks. Verify compatibility with vendor documentation for QSFP-DD passive breakouts and check that devices support the intended lane splitting and speed negotiation before deployment. Avoid routing through tight bends or sharp edges and maintain appropriate strain relief at connectors to preserve signal integrity.