WireGuard has a three byte block in its header which is not currently used by other clients. We decided to put our identifier in this region and still support messages from other WireGuard clients (albeit with less reliable routing than we can offer).
The Technical Challenges of Building Cloudflare WARP
If you have seen [our other post] you know that we released WARP to the last members of our waiting list today. With WARP our goal was to secure and improve the connection between your mobile devices and the Internet.
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