Arista Networks CAB-Q-S-3M Compatible 40G QSFP+ to 4 x 10G SFP+ Passive Copper Breakout Cable, 3m (10ft)

Product Highlights

• Compatible alternative to Arista Networks CAB-Q-S-3M
• 40G connectivity at 40Gbps
• Interface configuration: QSFP+ to 4 SFP+
• Fixed length and part number: 3m (10ft), CAB-Q-S-3M
• Conductor specification: 30AWG
• Minimum bend radius: 21mm

Specifications

Cable Construction and Routing

This assembly uses 30AWG conductors, PVC (OFNR) jacket, minimum bend radius 21mm. 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.

Position Within the Length Range

CAB-Q-S-3M occupies the middle of this family between CAB-Q-S-2M at 2m (7ft) and CAB-Q-S-4M at 4m (13ft). 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.

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 listed conductor specification is 30AWG; the minimum bend radius is 21mm; the jacket material is PVC (OFNR).

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

At 3m (10ft), this assembly can bridge non-aligned ports or adjacent racks while remaining a single direct-attach link. Support longer horizontal runs with suitable cable management and preserve space for cooling and future maintenance.

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. Quantity and any labeling instructions should be attached specifically to CAB-Q-S-3M.

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. Both connectors are examined before the operating test, which includes link stability and diagnostic indications.

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. 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.

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. Volume orders can include customer references on the labels and carton list.

Frequently Asked Questions