Important steps to consider before ordering DAC/AOC cables
Imagine a scenario where you want to implement a network topology using DAC cables. Let’s try to connect, for example Dell QLogic 57810S 10GB PCI card with an HP FlexFabric 5930 Switch using a 10-meter-long DAC cable.
After inserting the DAC cable in both equipment units, the network link doesn’t go up. Not trying to enable/disable port on the server or switch, nor physically pulling out and putting in the cable, doesn’t help to solve to issue.
The solution to this problem can be found in both the equipment documentation. On the datasheets, we can see that this exact QLogic PCI card supports only Passive Twinax (Copper) Direct Attach Cables (DAC) up to 7 metres. HP Switch supports DAC cables as well, but only up to 5 meters. For longer connections, this exact switch needs to be connected using an Active Optical Direct Attach Cable (AOC). So in this scenario, the only way to connect these units would be using a DAC cable over a shorter distance or connecting them using SFP+ transceivers with a patch cable.
So what are some essential steps that you should think about before ordering a DAC/AOC cable? As we can learn from the situation scenario above, it’s necessary to see if both equipment units you will be using the cable in support the type and length of cable you want to use. The best way to do it is by studying the datasheet of the equipment you will be using. The second step could be revising the pros and cons of both cables. DAC cables offer the client high data rates of 4Gbps to 10Gbps per channel, and at the same time are more cost-effective than using an AOC cable. On the other hand, AOC cables offer high data rates up to 40 Gbps with QSFP+, at the same time being lightweight and immune to electromagnetic energy.
If you have any other questions about DAC/AOC cables, please do not hesitate to contact us!
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Direct Attach Cables (DAC) – 10G to 800G
Direct Attach Copper (DAC) cables deliver high-speed connectivity for data centers and network equipment rooms where cost efficiency and low power consumption are priorities. These pre-terminated copper assemblies eliminate the need for separate transceivers, reducing both equipment costs and power draw compared to optical solutions. EdgeOptic's DAC portfolio spans 10G to 800G speeds, with passive cables reaching up to 7 meters for lower speeds and 3 meters for higher bandwidths. For connections requiring extended reach without transitioning to fiber, our active DAC options provide signal amplification to maintain data integrity over longer distances. When connecting equipment operating at different speeds—such as 100G switches to 25G servers or 40G infrastructure to 10G devices—our breakout DAC cables split high-bandwidth connections into multiple lower-speed ports, simplifying network architecture and reducing port costs. All EdgeOptic DAC cables are coded for compatibility with major networking vendors including Cisco, Juniper, HPE, Dell, and Mellanox. Our engineering team can also provide custom configurations with different vendor coding on each end—ideal for mixed-vendor environments in data center deployments. Contact us for compatibility questions or custom requirements.
Active Optical Cables (AOC) – 10G to 400G
Active Optical Cables (AOC) combine the simplicity of direct attach connectivity with the extended reach of fiber optics. Using integrated optical transceivers at each end, AOC cables transmit data over multimode fiber while maintaining a plug-and-play installation experience—no separate optics or fiber splicing required. EdgeOptic's AOC portfolio covers speeds from 10G to 400G with reach up to 100 meters, bridging the gap between short-reach copper DAC and long-haul single-mode fiber deployments. AOC cables are ideal for inter-rack connections, high-performance computing clusters, and any application requiring cable runs beyond copper limitations while avoiding the complexity of traditional fiber infrastructure. All our AOC cables feature DDM/DOM (Digital Diagnostic Monitoring) for real-time link health monitoring, enabling proactive network management and faster troubleshooting. The fiber-based design provides inherent immunity to electromagnetic interference, making AOC ideal for environments with high EMI or where cable routing runs near power systems. EdgeOptic AOC cables are coded for compatibility with leading vendors including Cisco, Juniper, HPE, Dell, Mellanox, and Intel. Custom coding for mixed-vendor environments is available upon request. Contact our team for specific compatibility requirements or assistance selecting the right AOC solution for your deployment.