Tailscale

[alimac]

Tailscale is a free service that helps you create secure private networks
Setting up a tailnet doesn’t require advanced networking expertise
It uses trusted encryption software and well-known identity providers

Info
I built my own secure network in the cloud to access my home PCs remotely - for free - ZDNET

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Tailscale: How it works

 

[CyborJaX]

Well I hope it changed from when I tried it, I had constant issues when trying to set my own Password I had to keep reverting back to default to get it to work, so I took it off. (That was the instruction given forum when trying to cure the issue)
Then I set up my own private ftp server work great on whatever machine and where ever I am.