Fortinet FN-CABLE-QSFP28-4SFP28-3.5 Compatible 100G QSFP28 4 x 25G NRZ to 4 x 25G SFP28 NRZ Passive Copper Breakout Cable, 3.5m (11ft)

This 3.5m (11ft) DAC cable is built for Fortinet equipment requiring the FN-CABLE-QSFP28-4SFP28-3.5 interface. The 100Gbps link uses QSFP28 to SFP28 and is supplied as one complete tested assembly.

OEM Part Number: FN-CABLE-QSFP28-4SFP28-3.5HT Part Number: FN-CABLE-QSFP28-4SFP28-3.5

Product Highlights

• Compatible alternative to Fortinet FN-CABLE-QSFP28-4SFP28-3.5
• 100G connectivity at 100Gbps
• Interface configuration: QSFP28 to SFP28
• Fixed length and part number: 3.5m (11ft), FN-CABLE-QSFP28-4SFP28-3.5
• Cable construction: Passive Twinax
• Conductor specification: 26AWG
• Maximum power consumption: ≤0.125W
• Minimum bend radius: 70mm

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.

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.

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 3.5m (11ft) length gives FN-CABLE-QSFP28-4SFP28-3.5 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.

FN-CABLE-QSFP28-4SFP28-3.5 occupies the middle of this family between FN-CABLE-QSFP28-4SFP28-3 at 3m (10ft) and FN-CABLE-QSFP28-4SFP28-5 at 5m (16ft). It adds 0.5m over the shorter option for extra routing clearance, while the next longer version adds another 1.5m. Measure the managed path and choose this version when its reach is sufficient without creating the slack associated with the longer assembly.

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 26AWG conductors, PVC (OFNR) jacket, minimum bend radius 70mm. 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 assembly is configured for equipment that recognizes FN-CABLE-QSFP28-4SFP28-3.5. Before shipment, we inspect both connectors and verify identification, link establishment and electrical continuity, link stability and diagnostic readouts. Host hardware and firmware revisions can affect third-party cable acceptance, so customers can provide the equipment model and software release for a pre-order compatibility review.

Quote HT part number FN-CABLE-QSFP28-4SFP28-3.5 with the required quantity. The 3.5m (11ft) 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.

Before packing, our team checks the cable jacket, connector boots, latches and identification of each assembly. The cable is then secured in a loose coil and protected against dust and connector impact. Neutral packaging, customer part-number labels and project-specific carton lists can be supplied on request.

Standard configurations normally ship within one to three working days. Worldwide courier, air freight and sea freight options are available, and shipments can also be sent on your own courier account or delivered to an appointed forwarder.