How does edge device capacity influence SD-WAN design?

• A. Edge capacity directly limits the number of tunnels, throughput, and security features; designs must respect device limits
• B. Edge capacity has no impact on tunnel count
• C. It only affects power consumption
• D. It affects only licensing

Answer: (D)

Edge device capacity sets the ceiling for what SD-WAN can deliver at the edge. The hardware determines how many VPN tunnels can be terminated, the maximum data throughput, and which security features you can run (such as encryption strength, firewall policies, and threat-inspection capabilities). Because of these limits, you size edge devices to handle expected branch counts, traffic patterns, and policy complexity with some headroom for growth. If you push beyond what the device can handle, performance degrades and some features may not be available or sustainable.

Licensing can influence which features you can enable or how many tunnels you’re allowed, but it doesn’t replace the fundamental constraint imposed by the hardware itself. The core design decision is driven by the edge capacity, so the design must respect those device limits to ensure reliable operation and meet performance targets.