virtualbox.org

When I install VirtualBox on two different machines on the same physical LAN, can I create a virtual network between these VMs by using settings within VBox itself, or would it be necessary to use some sort of supplementary programs, such as ssh, or socat, or other similar program? If it can be done with VBox alone, would these connections be encrypted? Perhaps someone can point to a link with information and discussion about this topic? Thanks.

That is not strictly possible with Virtualbox alone.
Is it possible with the help of the Virtual Distributed Ethernet project (VDE) that Virtualbox uses directly but only on Linux & FreeBSD host - see the User manual for it.

Otherwise If you want to keep it software and strictly in the VMs, you are bound to use any kind of VPN.
If you allow the hosts to "provide" the interface on which you would bridge the guest, any kind of tunneling server would do given they install a virtual NIC.

Thank you. That is what I needed. Looks like I have some homework to study, for a while. I would be interested in dialogue with anyone else who has implemented this procedure in any way.

If nobody turns up that has experience using it, I'm available tomorrow to help you implement it - never done it myself but always wanted it.
Shouldn't be too hard

Hi, noteirak.

Your offer to help is awesome. First I need to look at some of the background documentation to have a better overview of it before jumping in. When I have done that much, I will tug on your sleeve. I am traveling in the next few days and that should be a good time for me to read up. Talk to you later then!

Sure thing, just let me know when you're available.