Question: I recently found [Mouse without Borders](https://www.microsoft.com/en-us/download/details.aspx?id=35460) but this just works for Windows.

My question is now if there is something like that which works with Ubuntu with a secure connection.  

It should provide

* Mouse sharing
* keyboard sharing
* Clipboard sharing
* secure (encrypt data)

If possible for free.  

I would appreciate OpenSource

Answer: 
Looks like there is an app out there called Synergy. I'm just discovering this, so I know nothing about it. I just stumbled across this article: 
<http://www.linuxandubuntu.com/home/share-mouse-and-keyboard-with-your-windows-linux-machines-with-synergy-1-7-1>
Try with Barrier-KVM. This works perfectly for me. You can also use this with different subnets and different OS Platforms.