Arista Networks A-D400-Q400-20M Compatible 400G QSFP112 4 x 100G PAM4 to 400G QSFP-DD 8 x 50G PAM4 Active Optical Cable, 20m (66ft)

Product Highlights

• Compatible alternative to Arista Networks A-D400-Q400-20M
• 400G connectivity at 400Gbps
• Interface configuration: QSFP112 to QSFP-DD
• Fixed length and part number: 20m (66ft), A-D400-Q400-20M
• Cable construction: AOC
• Maximum power consumption: 10W (QSFP112 End) 14W (QSFP-DD End)
• Minimum bend radius: 30mm

Specifications

Signal and Lane Configuration

The listed modulation format is QSFP112-4x 100G-PAM4QSFP-DD-8x 50G-PAM4. Both host interfaces must be configured for the same aggregate rate and lane arrangement. A connector that fits mechanically does not by itself guarantee that the remote port supports this encoding or breakout mode.

Integrated Optical Assembly

The optical engines and fiber are permanently integrated into this AOC. There are no detachable optical modules to clean or exchange. Handle the complete assembly by its connector housings and cable, and keep both ends matched to the same interface specification.

Length Selection and Installation Planning

For this 20m (66ft) version, prepare the destination pathway before connecting either end. A longer assembly can cross separated equipment positions, but its weight and service slack must remain supported without blocking airflow. Handle the integrated optical cable and both optical engines as one factory-terminated product and never pull a connector into position by the cable. Within this family, A-D400-Q400-15M is shorter at 15m (49ft), while A-D400-Q400-25M is the next longer choice at 25m (82ft); comparing those two boundaries helps avoid both tension and unnecessary slack.

Position Within the Length Range

A-D400-Q400-20M occupies the middle of this family between A-D400-Q400-15M at 15m (49ft) and A-D400-Q400-25M at 25m (82ft). It adds 5m over the shorter option for extra routing clearance, while the next longer version adds another 5m. Measure the managed path and choose this version when its reach is sufficient without creating the slack associated with the longer assembly.

Interoperability and Configuration Checks

Check three layers before deployment: the host must accept the cable identification, the port must support the stated aggregate rate, and the lane configuration must match the attached interfaces. On breakout hardware, also confirm channelization and the mapping of every branch. These checks are particularly important when similar-looking ports operate at different speeds or under different firmware settings. For this assembly, the minimum bend radius is 30mm; the stated power consumption is 10W (QSFP112 End) 14W (QSFP-DD End); the jacket material is OFNP.

Power and Thermal Planning

The rated power consumption is 10W (QSFP112 End) 14W (QSFP-DD End). Include this load in the host-port power and thermal budget, especially in densely populated switches. Maintain front-panel clearance and do not bundle the cable so tightly that it obstructs airflow around the connectors.

Cable Construction and Routing

This assembly uses OFNP jacket, minimum bend radius 30mm. These mechanical characteristics affect how the cable should be dressed behind the equipment. Avoid sharp edges, excessive ties and repeated tight bends close to the connector boots.

Network and Protocol Considerations

The intended application is determined by the host interface and protocol support. Listed interface and protocol references include QSFP112 MSA, QSFP-DD MSA, IEEE802.3ck, IEEE802.3bs, CMIS 5.1. Confirm that the host firmware and port configuration support the same operating mode.

Ordering Information

Specify the OEM part number and fixed length, then provide the intended host configuration if the link uses channelized or breakout ports. Separate part numbers should be used for separate lengths. This gives the compatibility review enough information to check both the physical assembly and the intended operating mode. This page’s fixed configuration is 20m (66ft); another length must be quoted under its corresponding part number.

Arista Networks Compatibility and Factory Testing

The verification process combines digital identification with a live link test and diagnostic observation. Host model, hardware revision and software release are useful inputs because qualification behavior can change between platform generations; those details allow platform-specific requirements to be reviewed before the cable is packed. The check includes receive activity and diagnostic indications, followed by a final inspection of both ends.

Shipping and Lead Time

Available stock is generally dispatched within one to three working days after order confirmation, with production lead times advised for larger quantities. International express, air cargo and sea freight can be selected according to destination and carton volume; customer courier accounts and nominated forwarders are also accepted.

Quality Assurance and Packaging

Functional inspection covers identification, link establishment and the condition of both connector assemblies. The cable is then protected against dust and connector damage and packed without sharp bends. Labels can include the customer reference and host-platform note when requested for a controlled deployment. Neutral packaging and customer-specific packing documentation are available on request.

Frequently Asked Questions