In data centers, enterprise networks, and even high-performance computing clusters, high-speed interconnect cables are indispensable "capillaries." In short-distance interconnect scenarios, a pair of cables, each with its unique advantages, almost dominates the connection from inside the server rack to adjacent racks—these are DAC (Direct Connector Copper Cable) and AOC (Active Optical Cable). Often referred to as the "Golden Partner" in the industry, today we'll delve into the exceptional features of this combination.

Ⅰ.Comparison of DAC and AOC Transmission Solutions

(1)DAC (Direct Connector): Transmission is entirely electrical. The electrical pulses from the transmitting end travel directly through the copper cable to the receiving end without any conversion in between. This can be understood as "electrical signals taking a high-speed train"—the signal is fast for short distances, but it attenuates and becomes distorted over long distances.

(2)AOC (Active Optical Cable): Electrical → Optical → Electrical Conversion. The transmitting end modulates the electrical signal into an optical signal (VCSEL laser emits light), which is transmitted through optical fiber. The receiving end then converts the light back into an electrical signal. It's like "the electrical signal first takes an airplane (light), and then it's transferred back to ground transportation."

Ⅱ.How do these "Golden Partners" work together?

In actual data center deployments, they are divided into the following roles:

1.Within the same server rack (server ↔ top-mounted switch): Use DAC. Short distance (1-2 meters), lowest cost, lowest power consumption.

2.Between adjacent cabinets (top-rack switch ↔ top-rack switch/row-end switch): Use AOC. Distance 10-50 meters, requires lightweight cabling and interference resistance.

3.For longer distances (row end switch ↔ core switch): use optical modules + fiber optic cables. AOC's 100Mbps speeds are insufficient; gigabit-level long-distance transmission is required.