DAC (direct attach cable) cables and AOC (active optical cable) cables are two of the most common types of cables used to connect network switches or other devices. It is important to understand the differences between them. In this blog post, we will give a brief introduction to DAC cables and AOC cables, and explain which one is best for your needs.
High-speed and high-reliability interconnection and transmission are required between data centers, high-performance computers, and large-capacity storage devices. DAC and AOC are commonly used.
What is AOC cable?
Active Optical Cable, referred to as AOC, is translated as active optical cable. There are two modules at both ends of the AOC and a length of fiber in the middle (refer to Figure 3). There are optical transmitters and optical receivers on the circuit boards in the modules at both ends of the AOC. Their functions are to convert electrical signals into optical signals at the transmitting end, transmit them to the optical fiber, and convert the optical signals into electrical signals at the receiving end. Because it uses optical signal transmission, the transmission distance is longer than that of DAC, but due to the photoelectric conversion involved, the design and processing technology are more complicated, and the cost and power consumption are also higher.
Advantage:
• Light: Compared with ordinary cables, it is smaller and lighter.
• Strong ability to shield electromagnetic interference: AOC transmits signals through optical fibers. The optical fiber material is an insulating dielectric and is not easily affected by electromagnetic interference.
Disadvantage:
• Higher cost compared to DAC.
What is DAC Cable?
Direct Attach Cable, referred to as DAC. The DAC is divided into passive DAC (Passive Copper Cable) and active DAC (Active Copper Cable). The DAC transmits all electrical signals and does not involve the conversion of electricity to light or light to electricity.
Passive DACs use shielded differential copper cables, and there are no chips on the circuit boards at both ends. During the entire signal transmission process, no signal processing is performed. Passive DAC is the preferred solution for short-distance applications and is commonly used in data transmission between the same cabinet or adjacent cabinets in data centers. Its biggest features are low cost, ultra-low power consumption (less than 0.1 watts), and high reliability.
Advantage:
• Strong interchangeability: DAC cables and optical fiber transceivers can be interchanged and hot-swappable.
• Low cost: Copper cables are cheaper than optical fibers in both procurement and wiring costs, which can reduce the cost of use in general.
• Good heat dissipation: The DAC cable is composed of a copper core and has good heat dissipation.
Disadvantage:
• The transmission distance is limited, and the weight and volume are large.
