SSTP is a very nice, well performing Secure Socket Tunneling Protocol type VPN protocol. First designed and implemented by Microsoft to be used on Windows VPN servers, it is now available on all platforms.
It is secure because the traffic between the server and the client is always encrypted with SSL (just like https: for the web).
To install a SSTP client on a Ubuntu 18.04 box, I installed a few packages from a third party repository using the PPA info provided here which mainly instructed me to issue the following commands:
sudo add-apt-repository ppa:eivnaes/network-manager-sstp
sudo apt-get update
sudo apt-get install network-manager-sstp sstp-client
Thank you Kerem Yılmaz for providing the correct link to the new repo.
To create an SSTP connection, start “Settings”, select “Network” and click the “+” sign and now you can select “Point-to-point Tunneling Protocol (SSTP)”.
Enter your server name or address into “Gateway” box; leave NT Domain empty, set CA Certificate to “(None)”. No need to play with Advanced settings.
It works like a charm.