If you've ever set up a VPN on a VPS and watched it work perfectly for about two days before suddenly dying, you're not alone. I've been there — staring at connection timeouts, wondering if my server crashed, only to realize the network I'm on has started blocking my traffic. The problem isn't your VPN software. The problem is that VPN traffic is increasingly easy to fingerprint and block. The Root Cause: VPN Traffic Sticks Out Deep packet inspection (DPI) has gotten terrifyingly good. Even if your traffic is encrypted, the pattern of that traffic gives it away. OpenVPN has a recognizable handshake. WireGuard uses a fixed UDP port and has distinctive packet sizes. Even SSH tunnels exhibit telltale flow patterns. Here's what a typical blocked scenario looks like: Client → VPN Server (port 1194/UDP) ↓ DPI Firewall detects OpenVPN handshake pattern ↓ Connection RST or silently dropped Enter fullscreen mode Exit fullscreen mode The firewall doesn't need to decrypt anything.…