Cisco QSFP-4SFP25G-CU1M Compatible 100G QSFP28 4 x 25G NRZ to 4 x 25G SFP28 NRZ Passive Copper Breakout Cable, 1m (3ft)

The QSFP-4SFP25G-CU1M compatible DAC cable provides 100G connectivity for Cisco equipment over a fixed 1m (3ft) assembly. Both ends use the stated QSFP28 to SFP28 arrangement. It is inspected and functionally checked before packing, with handling guidance designed to protect the connectors during installation and later service.
OEM Part Number: QSFP-4SFP25G-CU1MHT Part Number: QSFP-4SFP25G-CU1M
Product Highlights
- Compatible alternative to Cisco QSFP-4SFP25G-CU1M
- 100G connectivity at 100Gbps
- Interface configuration: QSFP28 to SFP28
- Fixed length and part number: 1m (3ft), QSFP-4SFP25G-CU1M
- Cable construction: Passive Twinax
- Conductor specification: 30AWG
- Maximum power consumption: ≤0.125W
- Minimum bend radius: 60mm
Specifications
| HT Part Number | QSFP-4SFP25G-CU1M |
|---|---|
| Cisco Compatible | QSFP-4SFP25G-CU1M |
| Manufacturer | HT |
| Form Factor | QSFP28 to SFP28 |
| Max Data Rate | 100Gbps |
| Cable Type | Passive Twinax |
| Cable Length | 1m (3ft) |
| 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.
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
At 1m (3ft), QSFP-4SFP25G-CU1M is a practical choice for direct connections within one rack. Route the cable along the intended management path rather than pulling it diagonally across adjacent connectors, and leave enough clearance for insertion, removal and front-panel airflow.
Position Within the Length Range
QSFP-4SFP25G-CU1M occupies the middle of this family between QSFP-4SFP25G-CU50CM at 0.5m (2ft) and QSFP-4SFP25G-CU1-5M at 1.5m (5ft). 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.
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.
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. Both connectors are examined before the operating test, which includes link stability and diagnostic indications.
Frequently Asked Questions
Is this an original Cisco cable?
No. It is an HT-manufactured compatible alternative for equipment that specifies Cisco QSFP-4SFP25G-CU1M.
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. This page’s fixed configuration is 1m (3ft); 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.
