Arista Networks CAB-D-8S-400G-2M Compatible 400G QSFP-DD 8 x 50G PAM4 to 8 x 50G SFP56 50G PAM4 Passive Copper Breakout Cable, 2m (7ft)

This 2m (7ft) DAC cable is built for Arista Networks equipment requiring the CAB-D-8S-400G-2M interface. The 400Gbps link uses QSFP-DD to 8x SFP56 and is supplied as one complete tested assembly.

OEM Part Number: CAB-D-8S-400G-2MHT Part Number: CAB-D-8S-400G-2M

Product Highlights

• Compatible alternative to Arista Networks CAB-D-8S-400G-2M
• 400G connectivity at 400Gbps
• Interface configuration: QSFP-DD to 8x SFP56
• Fixed length and part number: 2m (7ft), CAB-D-8S-400G-2M
• Cable construction: Passive Breakout DAC
• Conductor specification: 28AWG
• Maximum power consumption: 0.1W (QSFP-DD End)0.1W (SFP56 Per End)
• Minimum bend radius: 39.5mm

The listed modulation format is QSFP-DD-8x 50G-PAM4SFP56-50G-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.

CAB-D-8S-400G-2M occupies the middle of this family between CAB-D-8S-400G-1.5M at 1.5m (5ft) and CAB-D-8S-400G-2.5M at 2.5m (8ft). It adds 0.5m over the shorter option for extra routing clearance, while the next longer version adds another 0.5m. Measure the managed path and choose this version when its reach is sufficient without creating the slack associated with the longer assembly.

The rated power consumption is 0.1W (QSFP-DD End)0.1W (SFP56 Per 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.

This assembly uses 28AWG conductors, PVC (OFNR) jacket, minimum bend radius 39.5mm. 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.

The intended application is determined by the host interface and protocol support. Listed interface and protocol references include QSFP-DD MSA, SFF-8432, IEEE 802.3bs-400GAUI-8, IEEE802.3cd-50GAUI-1, CMIS 4.0, SFF-8472. Confirm that the host firmware and port configuration support the same operating mode.

The QSFP-DD to 8x SFP56 configuration divides the high-speed interface into multiple lower-speed connections. Verify the upstream lane assignment, downstream port speeds and breakout setting on the host before connecting the assembly. Each branch must attach to the correct remote interface.

A passive DAC has no separate optical conversion stage. Its low-power, low-latency operation is useful for short equipment links, but the assembly must remain within the length and signaling mode accepted by both hosts.

CAB-D-8S-400G-2M provides 2m (7ft) for connections between separated rack units or nearby equipment positions. Plan the route around cable managers and power cords, keeping the assembly free from connector strain while avoiding a large obstruction in the airflow path.

For this Arista Networks application, testing combines digital identification with actual traffic-link verification and electrical continuity, link stability and diagnostic readouts. Both ends are inspected for latch, boot and connector damage. If the project uses a specific hardware revision or a channelized port, send those details so that the intended configuration can be reviewed before shipment.

When ordering, specify CAB-D-8S-400G-2M, cable length 2m (7ft) and the host platform. This allows our team to verify both the physical assembly and the compatibility requirement before production. Neutral labeling and customer packing lists can be arranged for volume orders.

Every CAB-D-8S-400G-2M compatible assembly undergoes link testing, compatibility verification and visual inspection. The 2m (7ft) cable is coiled without exceeding its minimum bend radius, fitted with connector protection and packed in an anti-static bag or protective tray before cartoning. Project labels and packing lists are available for volume orders.

Available stock is usually packed and handed to the carrier within one to three working days. Delivery can be arranged by international express, air cargo or sea freight, with tracking details supplied after dispatch. Freight-collect shipments and delivery to a customer warehouse or forwarder can also be coordinated.