Arista Networks CAB-Q-4S-100G-2M Compatible 100G QSFP28 4 x 25G NRZ to 4 x 25G SFP28 NRZ Passive Copper Breakout Cable, 2m (7ft)

Product Highlights

• Compatible alternative to Arista Networks CAB-Q-4S-100G-2M
• 100G connectivity at 100Gbps
• Interface configuration: QSFP28 to SFP28
• Fixed length and part number: 2m (7ft), CAB-Q-4S-100G-2M
• Cable construction: Passive Twinax
• Conductor specification: 30AWG
• Maximum power consumption: ≤0.125W
• Minimum bend radius: 60mm

Specifications

Signal and Lane Configuration

The listed modulation format is QSFP28-4x 25G-NRZ SFP28-1x 25G-NRZ. 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.

Network and Protocol Considerations

The intended application is 100G to 4x 25G Ethernet, Data Centers. Listed interface and protocol references include IEEE 802.3, QSFP28 MSA, SFF-8665. Confirm that the host firmware and port configuration support the same operating mode.

Breakout Port Mapping

The QSFP28 to SFP28 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

CAB-Q-4S-100G-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.

Position Within the Length Range

CAB-Q-4S-100G-2M occupies the middle of this family between CAB-Q-4S-100G-1.5M at 1.5m (5ft) and CAB-Q-4S-100G-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.

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 30AWG; the minimum bend radius is 60mm; the stated power consumption is ≤0.125W; the jacket material is PVC (OFNR).

Power and Thermal Planning

The rated power consumption is ≤0.125W. 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.

Cable Construction and Routing

This assembly uses 30AWG conductors, PVC (OFNR) jacket, minimum bend radius 60mm. 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.

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 2m (7ft); 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. Neutral packaging and customer-specific packing documentation are available on request.

Frequently Asked Questions

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. 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.