A Copper Direct Attach Cable (DAC) is a physical copper cable with transceivers on either side to connect network devices directly and does not require a separate optic for that function. Owning the strengths and weaknesses of the cable choices—SFP+ DAC cables or optical modules—will help you streamline your decision-making process to determine which solution is best for your circumstances. By the end of our discussion, you will be able to draw a comparison between both technologies. DAC is a copper-based direct attach cable without optical conversion, while AOC uses optical fiber for transmission. Both are plug-and-play and support hot-swappable modules such as SFP+, QSFP+, QSFP28. DACs can be further classified into Active Copper Cables (ACC), Active Electrical Cables (AEC), and passive DACs. This delivers a convenient all-in-one solution, built into one cable. Copper passive cables are bulky and numerous. A mating interface is where the two separable pieces of a connector system that come together to form an interconnect.
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