Cisco QSFP-4SFP25G-CU50CM Compatible 100G QSFP28 4 x 25G NRZ to 4 x 25G SFP28 NRZ Passive Copper Breakout Cable, 0.5m (2ft)

This 0.5m (2ft) DAC assembly is made for installations that call for Cisco QSFP-4SFP25G-CU50CM at 100G. The QSFP28 to SFP28 connectors and cable arrive as one complete product, ready for a direct link between suitable ports. Field-handling guidance, exact specifications and pre-packing functional checks apply to the part number shown here.
OEM Part Number: QSFP-4SFP25G-CU50CMHT Part Number: QSFP-4SFP25G-CU50CM
Product Highlights
- Compatible alternative to Cisco QSFP-4SFP25G-CU50CM
- 100G connectivity at 100Gbps
- Interface configuration: QSFP28 to SFP28
- Fixed length and part number: 0.5m (2ft), QSFP-4SFP25G-CU50CM
- Cable construction: Passive Twinax
- Conductor specification: 30AWG
- Maximum power consumption: ≤0.125W
- Minimum bend radius: 60mm
Specifications
| HT Part Number | QSFP-4SFP25G-CU50CM |
|---|---|
| Cisco Compatible | QSFP-4SFP25G-CU50CM |
| Manufacturer | HT |
| Form Factor | QSFP28 to SFP28 |
| Max Data Rate | 100Gbps |
| Cable Type | Passive Twinax |
| Cable Length | 0.5m (2ft) |
| Wire AWG | 30AWG |
| Minimum Bend Radius | 60mm |
| Power Consumption | ≤0.125W |
| Power Supply | 3.3V |
| MTBF | =50 Million Hours |
| Jacket Material | PVC (OFNR) |
| Commercial Temperature Range | 0 to 70°C (32 to 158°F) |
| Modulation Format | QSFP28-4x 25G-NRZ SFP28-1x 25G-NRZ |
| Media | Copper |
| Application | 100G to 4x 25G Ethernet, Data Centers |
| Protocols | IEEE 802.3, QSFP28 MSA, SFF-8665 |
Cisco OEM Reference
Cisco defines QSFP-4SFP25G-CUxM as a 100G QSFP to four 25G SFP passive copper breakout assembly. One end connects to a 100G QSFP port and the four branches connect to 25G interfaces on a switch or server. Correct channelization and lane mapping are essential for this HT compatible version as well.
Field Installation and Maintenance
Inspect the route and both connectors before installation, then support the cable without pulling on either connector housing. During maintenance, release the latch properly rather than using the cable as a handle. Keep protection on unused ends, and if the assembly is removed for later use, coil it loosely and record its part number so the same length can be returned to service. 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).
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.
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.
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
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 QSFP-4SFP25G-CU50CM; even a short assembly must retain the specified bend radius and should never be pulled tight behind the equipment.
Position Within the Length Range
QSFP-4SFP25G-CU50CM 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 QSFP-4SFP25G-CU1M at 1m (3ft), adding 0.5m for a less direct routing path; selecting it unnecessarily would leave more cable to dress.
Quality Assurance and Packaging
The cable and both connectors are inspected before a functional link test. Connector protection and bend-safe packing reduce handling damage during transport and storage. Customer or site labels can be added for field inventories, with different lengths separated to simplify issue and return of spare assemblies. Neutral packaging and customer-specific packing documentation are available on request.
Cisco Compatibility and Factory Testing
A field-ready cable needs both correct identification and a stable operating link. Our pre-packing check therefore includes the connectors, host recognition and link behavior. For equipment with uncertain revision history, providing the host model and software release helps identify compatibility requirements before the assembly reaches the installation site. Where supported by the host, link stability and diagnostic indications are reviewed together with the established link.
Frequently Asked Questions
Is this an original Cisco cable?
No. It is an HT-manufactured compatible alternative for equipment that specifies Cisco QSFP-4SFP25G-CU50CM.
Will any matching connector operate at the same speed?
Not necessarily. Both hosts must support the stated rate, identification, lane mapping and any required breakout configuration; mechanical compatibility alone is insufficient.
What details assist a compatibility review?
Provide the equipment manufacturer, model, port type, hardware revision and software release, together with the OEM reference, required length and quantity.
How should an unused assembly be stored?
Protect both connector ends, keep the cable in a loose bend-safe coil and retain its part-number label so the length and compatibility identity remain traceable.
Ordering Information
Request the cable by its exact part number and length, and state the equipment model if compatibility confirmation is needed. Site orders can list quantities by rack or installation team. Any requested label should retain the part number so a removed or spare cable can still be identified accurately. Quantity and any labeling instructions should be attached specifically to QSFP-4SFP25G-CU50CM.
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.
