Ubiquiti UACC-DAC-QSFP28-0.5M-10 100GBase Direct Attach Cable
Overview
The Ubiquiti UACC-DAC-QSFP28-0.5M-10 is a 100GBase direct attach cable (DAC) engineered for short-reach, high-speed interconnects in data center and enterprise network environments. At 0.5 meters (1.6 feet), this cable provides cost-effective, low-latency connectivity between QSFP28-equipped switches, routers, and line cards operating at 100 Gbps data rates. By eliminating the need for separate optical transceivers, the UACC-DAC-QSFP28-0.5M-10 reduces operational complexity, cuts capital cost, and minimizes latency — critical factors in rack-dense environments where equipment is tightly spaced.
Key Features
- 100GBase Passive DAC Technology: Direct copper connection eliminates transceiver overhead. Passive design means no power consumption, no electronics to fail, and no compatibility matrices to manage — plug both ends into any QSFP28 port rated for 100GBase operation and signal passes through. Particularly valuable in densely populated switch fabrics where every watt and every millisecond of latency matter.
- 0.5-Meter Length: Short reach is by design. This cable is optimized for adjacent equipment stacking, top-of-rack (ToR) switch interconnects, and same-rack fabric connections. If equipment spans multiple racks or across greater distances, optical transceivers and fiber are the correct choice — this DAC is not rated for longer runs and will degrade signal quality beyond 0.5 meters.
- QSFP28 Connector Compatibility: Both ends terminate in standard QSFP28 connectors. Verify your switch, router, or line card actually supports 100GBase QSFP28 (not all QSFP28 ports do — some are rated for 10/25/40 Gbps only). Check equipment datasheets before ordering.
- Passive, No Power or Configuration: No firmware, no drivers, no power draw. Deploy it like any other copper cable — pull, insert, lock. Reduces commissioning friction in large fabric refreshes.
- Ubiquiti Quality Standards: Built to the same durability expectations as Ubiquiti infrastructure products. Suitable for deployment in rack environments and equipment stacking scenarios where cables may encounter routine handling and environmental vibration.
Integration & Compatibility
The UACC-DAC-QSFP28-0.5M-10 works with any device featuring QSFP28 ports rated for 100GBase operation — Ubiquiti UniFi switches, third-party enterprise switches, routers, and line cards included. Verify that your target equipment supports 100GBase on the QSFP28 ports you intend to use; many enterprise switches support mixed speeds (10/25/40/100 Gbps) on the same port type, so port capability must be confirmed in the equipment datasheet before purchase. Suitable for rack environments, equipment stacking, and adjacent-equipment connections where short cable runs are required. Not intended for cross-rack or long-distance links; fiber optics with separate transceivers are the correct architecture for longer distances.
When to Choose a Different Approach
If your fabric spans multiple racks or requires runs longer than 0.5 meters, consider optical transceiver solutions with single-mode or multi-mode fiber. If your target switch ports are rated for lower speeds (10/25/40 Gbps), confirm QSFP28 100GBase support before deploying this cable. For shorter, lower-speed interconnects within a single cabinet, standard copper interconnects may be more cost-effective.
Frequently Asked Questions
Q: Will the UACC-DAC-QSFP28-0.5M-10 work with my Ubiquiti UniFi switch?
A: Yes, provided your UniFi switch model includes 100GBase QSFP28 ports. Check the switch datasheet to confirm 100GBase capability on the port you intend to use; not all QSFP28 ports on all switches support 100 Gbps.
Q: Can I use this cable for longer runs between distant equipment?
A: No. The UACC-DAC-QSFP28-0.5M-10 is rated for 0.5 meters only. Longer runs will result in signal degradation and potential link errors. Use fiber optics with transceivers for distances beyond 0.5 meters.
Q: Does the cable require any configuration or drivers?
A: No. This is a passive direct attach cable — simply insert both connectors into QSFP28 ports and the link will negotiate automatically, provided both ports support 100GBase.
Q: What is the power consumption of this cable?
A: Zero. Passive design means no power draw. The cable is purely copper connectivity with no active electronics.
Q: Is the UACC-DAC-QSFP28-0.5M-10 compatible with non-Ubiquiti equipment?
A: Yes. Any switch, router, or line card with QSFP28 ports rated for 100GBase operation will work with this cable. Ubiquiti does not lock DAC compatibility to its own equipment.
Ted PerryPerspective based on aggregated IP Security Depot and affiliated engineering team experience.
The UACC-DAC-QSFP28-0.5M-10 is the right tool for one specific job: dense, short-reach fabric interconnects inside a single rack or between adjacent cabinets. At 0.5 meters and passive design, it eliminates transceiver cost, latency, and power overhead — but only if your equipment actually supports 100GBase on QSFP28. That last bit trips people up.
Technical Highlights:
- Passive DAC Architecture: No transceiver, no power consumption, no firmware. Copper-only signal path means lower total cost of ownership and zero compatibility risk once you've verified port speed capability.
- 100GBase Full-Duplex Performance: Standard 100GBase-CR4 passive DAC spec delivers full 100 Gbps bidirectional throughput with latency measured in nanoseconds — meaningfully lower than active transceiver solutions over these distances.
- 0.5-Meter Length Constraint: This is both feature and limitation. Perfect for top-of-rack fabric and tightly packed switch stacks; completely wrong for cross-rack or multi-cabinet deployments. Attempting longer runs will degrade signal integrity and cause link flapping.
Deployment Considerations:
- Verify 100GBase QSFP28 support on target ports before ordering. Many enterprise switches support mixed speeds on QSFP28 — check the equipment datasheet. A port rated for 10/25/40 Gbps will not reliably carry 100GBase traffic on this cable.
- Cable length is a hard boundary. If you need more than 0.5 meters, abandon passive DAC entirely and move to optical transceivers with single-mode or multi-mode fiber. Trying to extend passive DAC beyond rated distance is a false economy.
Deploy the UACC-DAC-QSFP28-0.5M-10 in hyperscale or enterprise fabric refreshes where equipment lives within arm's reach and 100GBase port capability is confirmed. Skip it entirely if your topology requires longer interconnects or if your switch ports are spec'd for 40 Gbps or lower.
