DAC vs. AOC Cables | A Guide to Avoiding Pitfalls in Data Center Cabling ✨
Networkers, take my advice! 🤯 When cabling data centers and AI clusters, choosing the wrong DAC or AOC cable can make maintenance a nightmare later on… I’ve compiled a comprehensive comparison and selection guide—even beginners can understand it instantly, so you’ll never waste money again!
First, understand the differences between the basics:
🔌 DAC Cable = Direct Attach Cable
It relies on copper transmission, requires no electro-optical conversion, comes with built-in connectors, and is plug-and-play! There are passive (super cheap) and active (supports slightly longer distances) versions. It’s ideal for short distances, low cost, and low latency—the top choice for interconnecting within racks.
💡 AOC Cable = Active Optical Cable
Fiber optic cable + built-in optical module. Performs electrical-to-optical-to-electrical conversion, making it completely immune to electromagnetic interference! Lightweight and slim, with maximum transmission distance. A must-have for cross-rack and cross-floor connections, and incredibly stable even in high-interference environments.
🔥 Key Comparison Metrics
▫️ Transmission Distance: DAC ≤ 15m (Passive ≤ 7m) | AOC up to 300m—go with AOC for medium to long distances
▫️ Cost: DAC is extremely cost-effective (1/2 to 1/5 the price of AOC) | Choose DAC for short distances; AOC saves more in the long run for long distances
▫️ Interference Resistance: DAC is susceptible to electromagnetic interference | AOC is completely immune—choose it for industrial server rooms or near high-power equipment
▫️ Cabling: DAC is thick, heavy, and difficult to bend | AOC is slim and lightweight—a lifesaver for high-density racks
📌 Quick Selection Guide
✅ When to choose DAC:
• Short-distance connections within a rack or between adjacent racks (≤7m)
• Limited budget, seeking high cost-effectiveness
• Sensitive to latency and power consumption (e.g., financial trading, high-performance computing)
✅ When to choose AOC:
• Cross-rack or cross-floor connections (＞7m, especially 20m+)
• High electromagnetic interference in the data center (near large equipment)
• High-density cabling (hyperscale data centers, AI computing clusters)
Final Takeaway📝: There’s no “better” option—only the right fit! For short distances, DACs save money and hassle; for medium to long distances, AOCs prioritize reliability. Avoid the pitfalls of “price-only” decisions and “blindly chasing high speeds,” and your cabling efficiency will double instantly～
