| These services do a couple of things: 1. They provide a VPN for your device to their server. 2. They then map that device to a public IPv4 address they own. The address is not static, but TailScale solves for that with internal DNS. 3. The free tier allows X number of devices to connect via a single account. I am not sure how many. Maybe 6, maybe 20. These devices are able to access each other on a private network only available from the VPN. TailScale calls that a TailNet. 4. They have internal DNS for the TailNet, so that you can map a name to one of those IPv4 addresses they provide and connect to something like http://server 5. I have not tried the others, but the TailScale magic DNS does not fully work on iOS. On iOS its all or nothing in that once their DNS is enabled its all you can access until your bring TailScale down on your device. I don't have this problem on my desktops (Windows or Linux) so my desktops are always connected. 6. NordVPN also provides these same capabilities, but they do not have a free tier. I don't know if they up charge for this capability above standard VPN. 7. Most all of these solutions seem to be based on WireGuard. WireGuard is an open source VPN solution, but it does not provide the extra services: IP address, DNS, service accounts, private network. In summary, TailScale provides a VPN to a private cluster, your private cluster, that can be accessed from any network, due to the public IP, so long as the given device is on the same VPN account or has received an invitation from that account. |