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.

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.

Rack Layout and Service Access

Plan the managed route before removing the connector protection. The cable should reach both ports without tension while leaving enough space to release the latches and service adjacent interfaces. Support the run through the intended managers, keep the connector boots clear of sharp edges and avoid storing excess length in a tight coil behind warm exhaust air. For this assembly, the listed conductor specification is 26AWG; the minimum bend radius is 28mm; 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.

Quality Assurance and Packaging

The completed cable is inspected at both ends, functionally tested and coiled with bend-safe slack. Protective packaging keeps the latches and boots from taking impact, while optional project labels can identify the two endpoint locations for easier field service. Standard protective packing is used by default, with project documentation arranged when requested.

Arista Networks Compatibility and Factory Testing

Compatibility is verified as part of a complete installation check: connector inspection, host identification and an operating link. The physical cable is evaluated together with the expected OEM identity, because a connector that fits is not sufficient evidence that the host will accept and operate the assembly correctly. Both connectors are examined before the operating test, which includes link stability and diagnostic indications.

Frequently Asked Questions

Ordering Information

When requesting this assembly, include the exact part number and length together with the destination port types. For a rack installation, a simple port-to-port list helps us keep different lengths separate and allows any requested labels to correspond with the actual installation sequence. This page’s fixed configuration is 4m (13ft); another length must be quoted under its corresponding part number.

Shipping and Lead Time

Standard configurations normally ship within one to three working days, while production quantities are confirmed with the order. Delivery can be arranged by courier, air freight or sea freight, and goods may instead be handed to an appointed forwarder or shipped on the customer’s courier account.