Arista Networks CAB-Q-S-4M Compatible 40G QSFP+ to 4 x 10G SFP+ Passive Copper Breakout Cable, 4m (13ft)

Product Highlights

• Compatible alternative to Arista Networks CAB-Q-S-4M
• 40G connectivity at 40Gbps
• Interface configuration: QSFP+ to 4 SFP+
• Fixed length and part number: 4m (13ft), CAB-Q-S-4M
• Conductor specification: 26AWG
• Minimum bend radius: 28mm

Specifications

Cable Construction and Routing

This assembly uses 26AWG conductors, PVC(OFNR) jacket, minimum bend radius 28mm. 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 SFF-8436, SFF-8431 and QSFP+ MSA. Confirm that the host firmware and port configuration support the same operating mode.

Breakout Port Mapping

The QSFP+ to 4 SFP+ 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.

Passive Copper Operation

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.

Length Selection and Installation Planning

The 4m (13ft) length gives CAB-Q-S-4M more freedom for adjacent-rack and row-end deployments. Longer copper runs need particular attention to routing weight and bend control; the DAC specification and host support must still match the intended link.

Position Within the Length Range

CAB-Q-S-4M occupies the middle of this family between CAB-Q-S-3M at 3m (10ft) and CAB-Q-S-5M at 5m (16ft). It adds 1m over the shorter option for extra routing clearance, while the next longer version adds another 1m. Measure the managed path and choose this version when its reach is sufficient without creating the slack associated with the longer assembly.

Mixed-Vendor Network Operation

A mixed-vendor link should be documented at both ends, not treated as one generic connection. Confirm which OEM identity each host expects and whether the two ends use the same compatibility requirement. The related brand links below help locate equivalent-length assemblies, while the physical form factor and lane arrangement must still agree across the complete path. For this assembly, the listed conductor specification is 26AWG; the minimum bend radius is 28mm; the jacket material is PVC(OFNR).

Arista Networks Compatibility and Factory Testing

Testing addresses the brand-specific identification as well as the operating link and available diagnostics. The same physical cable family can require a different host identity for another equipment vendor, so the intended platform should be supplied when a deployment combines multiple brands or unusual hardware revisions. The check includes link stability and diagnostic indications, followed by a final inspection of both ends.

Ordering Information

For mixed-vendor projects, identify the equipment at both ends along with the OEM reference, length and quantity. Order each compatibility version under its own part number. If spare assemblies are required, list them separately so labels and test records remain unambiguous. This page’s fixed configuration is 4m (13ft); another length must be quoted under its corresponding part number.

Quality Assurance and Packaging

Both ends are inspected and the complete assembly is powered up for a functional check before packing. Connectors are protected individually and the cable is secured without tight bends. Optional labels can distinguish host brand, OEM reference and length for easier spares management. Volume orders can include customer references on the labels and carton list.

Frequently Asked Questions

Shipping and Lead Time

Standard configurations normally ship within one to three working days, while production quantities are confirmed with the order. 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.