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.

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.

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

Longer assemblies require disciplined cable dressing. For A-D400-Q400-20M at 20m (66ft), use the intended managers rather than a diagonal route across the rack, and leave enough space to release each connector. Any service allowance should be loose and supported, with the integrated optical cable and both optical engines protected throughout the path. 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.

High-Density Rack Integration

In a densely populated rack, connector access and airflow are part of the link design. Choose the shortest length that follows the managed path comfortably, avoid tight bundles around the connector housings and preserve room for latch operation. Where power consumption is listed, include every populated interface in the host thermal budget rather than assessing a single cable in isolation. 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.

Quality Assurance and Packaging

Each assembly receives a visual connector inspection and functional link check before it is coiled and protected. Packaging is selected to avoid compressing the cable into a tight bundle, and optional rack-based labels help maintain an orderly installation when many identical interfaces are populated together. Neutral packaging and customer-specific packing documentation are available on request.

Ordering Information

Provide the exact part number, length, quantity and target interface density. For multi-rack projects, list each length separately and identify any preferred carton grouping. Host model and software information can be included for a compatibility review before production or dispatch. Keep A-D400-Q400-20M associated with 20m (66ft) throughout the order and receiving record.

Arista Networks Compatibility and Factory Testing

The assembly is evaluated for host recognition and stable link operation, with diagnostics checked where the interface provides them. This approach verifies more than electrical or optical continuity. Exact platform and firmware information remains valuable in high-density deployments because port mode and qualification policy can differ within the same connector family. The check includes receive activity and diagnostic indications, followed by a final inspection of both ends.

Frequently Asked Questions

Shipping and Lead Time

Standard configurations normally ship within one to three working days, with production quantities confirmed at order stage. Worldwide courier services are available, with air or sea freight for consolidated shipments; freight-collect delivery and coordination with a customer’s logistics provider can be arranged.