Direct Attach Cable Digitus 40G QSFP+ to 4XSFP+ 1m

The Digitus Direct Attach Cable 40G QSFP+ to 4xSFP+ (1 m, model DN-81321) is a passive breakout cable designed for high-density data centre connections. It provides one QSFP+ connector that breaks out to four SFP+ connectors, supporting 40G Ethernet and interoperability between 40G and 4×10G links. The cable is intended for short-range interconnects such as switch-to-switch, switch-to-server or server-to-storage within racks and row-based topologies.

Advantages

This breakout DAC offers high signal integrity and a compact 1 m length for convenient routing in dense rack environments. It operates from a single +3.3 V power supply and supports per-channel data rates up to 3.125 Gbps, enabling reliable 40G to 4×10G conversion. The cable is compliant with the SFF-8436 specification and is specified for operation in temperatures from 0 ℃ to 70 ℃.

Suitable for

• Data centre switch-to-switch connections
• Switch-to-server links in high-performance computing
• Server-to-NAS or storage interconnects within racks
• Short-reach breakout applications requiring 40G to 4×10G interoperability

Key specifications

• Model: DN-81321
• Type: Passive QSFP+ to 4×SFP+ direct attach cable (DAC)
• Length: 1 m
• Standards: Compliant with SFF-8436
• Data rate per channel: Up to 3.125 Gbps
• Aggregate: 40G Ethernet (supports 40G ↔ 4×10G interoperability)
• Power: Single +3.3 V supply
• Operating temperature: 0 ℃ to 70 ℃

How to use

Connect the QSFP+ end to a host or switch QSFP+ port and insert the four SFP+ ends into the corresponding SFP+ ports on the receiving devices. Ensure ports are rated for direct-attach copper if required and that the connected equipment supports the intended 40G or 10G modes. Route the 1 m cable without sharp bends and secure it to avoid strain on the connectors. Verify link status and speed settings on the connected hardware after installation.

Recommendations

Use this 1 m DN-81321 breakout DAC for short-reach, high-density connections inside racks or short patching between adjacent devices. Avoid exposure to temperatures outside the specified 0 ℃–70 ℃ range and prevent excessive tensile force or tight bends to maintain electrical performance and connector integrity.