To use Tailscale, you can install the client on each node, but for cases like embedded devices or existing VPCs, a subnet router is more practical. A subnet router allows devices to communicate using NAT traversal technology, whether running Tailscale or not. In this guide, we explain how to set up and configure subnet routers on Windows and Linux. Subnet routers provide an easy way to connect devices without installing the Tailscale client on each one, making it ideal for testing or hooking up large networks like AWS VPCs. Tailscale is free for personal use, and devices behind a subnet router don’t count towards the device limit.
https://tailscale.com/blog/subnet-router-video