Relay
The TunTun relay (tuntun-relay) is a self-hosted edge server that terminates public tunnels. Agents establish reverse tunnels to the relay, and the relay accepts public HTTPS (and TCP) connections and forwards them to the appropriate agent.
How it competes
The relay competes with Cloudflare Tunnel's edge network and ngrok's infrastructure. The difference is that you own and operate the relay servers. You control the DNS, the certificates, the geographic placement, and the capacity.
Architecture
The relay registers itself with the control plane via WebSocket. When a tunnel is created, the control plane assigns it to a relay and provides the agent with the relay address and auth token. The agent establishes a reverse QUIC connection to the relay. Public traffic arrives at the relay and is forwarded through this reverse connection.