Arista Networks CAB-Q-4S-100G-0.5M Compatible 100G QSFP28 4 x 25G NRZ to 4 x 25G SFP28 NRZ Passive Copper Breakout Cable, 0.5m (2ft)

The CAB-Q-4S-100G-0.5M cable offers a direct QSFP28 to SFP28 connection at 100Gbps. Its 0.5m (2ft) length and DAC construction are intended for Arista Networks equipment, with no separate transceiver-and-patch-cord assembly required.

OEM Part Number: CAB-Q-4S-100G-0.5MHT Part Number: CAB-Q-4S-100G-0.5M

Product Highlights

• Compatible alternative to Arista Networks CAB-Q-4S-100G-0.5M
• 100G connectivity at 100Gbps
• Interface configuration: QSFP28 to SFP28
• Fixed length and part number: 0.5m (2ft), CAB-Q-4S-100G-0.5M
• Cable construction: Passive Twinax
• Conductor specification: 30AWG
• Maximum power consumption: ≤0.125W
• Minimum bend radius: 60mm

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.

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.

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-4S-100G-0.5M; even a short assembly must retain the specified bend radius and should never be pulled tight behind the equipment.

CAB-Q-4S-100G-0.5M is the shortest of 8 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-4S-100G-1M at 1m (3ft), adding 0.5m for a less direct routing path; selecting it unnecessarily would leave more cable to dress.

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.

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.

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.

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.

Our compatibility setup for Arista Networks CAB-Q-4S-100G-0.5M is checked together with the physical 0.5m (2ft) assembly. Factory verification covers connector condition, host identification, error-free link establishment and electrical continuity, link stability and diagnostic readouts. Providing the exact host model and firmware release helps us identify platform-specific requirements before production.

Quote HT part number CAB-Q-4S-100G-0.5M with the required quantity. The 0.5m (2ft) length is fixed for this part number; if a different length is needed, select its corresponding page and OEM reference from the length list above. Standard HT labels and project-specific packaging are available.

Quality control includes connector appearance, cable identification and functional verification. Packing materials are selected to keep the connector housings and cable boots from taking impact during transport, and the coil is not compressed into an undersized bundle. Volume orders can include customer-specific labels and packing documentation.

Available stock is usually packed and handed to the carrier within one to three working days. Delivery can be arranged by international express, air cargo or sea freight, with tracking details supplied after dispatch. Freight-collect shipments and delivery to a customer warehouse or forwarder can also be coordinated.