Arista Networks CAB-Q-S-0.5M Compatible 40G QSFP+ to 4 x 10G SFP+ Passive Copper Breakout Cable, 0.5m (2ft)

Product Highlights

• Compatible alternative to Arista Networks CAB-Q-S-0.5M
• 40G connectivity at 40Gbps
• Interface configuration: QSFP+ to 4 SFP+
• Fixed length and part number: 0.5m (2ft), CAB-Q-S-0.5M
• 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.

Structured Pathways and Serviceability

Treat the direct-attach assembly as part of the permanent pathway plan even when the link is expected to be temporary. Follow the intended horizontal and vertical managers, maintain the specified bend radius and leave service access around both ports. A small, supported service allowance is preferable to excess slack concealed inside a rack or placed under cable-tie pressure. 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

The 0.5m (2ft) length is suited to closely aligned ports where excessive slack would obstruct airflow or complicate dressing. Measure the actual port-to-port path before choosing CAB-Q-S-0.5M; even a short assembly must retain the specified bend radius and should never be pulled tight behind the equipment.

Position Within the Length Range

CAB-Q-S-0.5M is the shortest of 7 verified length options in this family. It is the preferred choice when the port positions are close and cable slack must be kept to a minimum. The next option is CAB-Q-S-1M at 1m (3ft), adding 0.5m for a less direct routing path; selecting it unnecessarily would leave more cable to dress.

Ordering Information

Include the part number, fixed length, quantity and required pathway or rack grouping in the order information. The host model and firmware release are useful for change-controlled deployments. Different lengths should remain separate order lines so delivered labels and packing records agree with the pathway plan. Quantity and any labeling instructions should be attached specifically to CAB-Q-S-0.5M.

Arista Networks Compatibility and Factory Testing

Verification covers the physical connectors, expected host identity and an operating link with available diagnostic indications. We distinguish this complete check from a simple continuity test. Platform model and software release can be reviewed in advance where the installation has strict documentation or change-control requirements. Both connectors are examined before the operating test, which includes link stability and diagnostic indications.

Shipping and Lead Time

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

After connector inspection and link verification, the assembly is coiled without tight bends and packed with end protection. Labels can cross-reference the customer cable schedule, OEM part number and length. This supports both receiving checks and later moves, adds or changes. Neutral packaging and customer-specific packing documentation are available on request.

Frequently Asked Questions