virtualbox.org

I have VirtualBox running some VMs for me currently and all is working well. My physical network is a single 1Gb NIC currently to the outside world, but I'm wondering if I can increase in-band bandwidth between systems on the host using a secondary Host Only network that can run at a faster speed. Currently I only see options for 1Gb virtual NICs in the network setup as well as a "virtio-net". These all represent in the OS as 1Gb NICs and are therefore logically limited to 1Gb throughput. Is there a way to do 10Gb Host Only virtual NICs?

The speed settings of a virtual NIC are not relevant. The physical hardware determines the actual speed. If the case of purely virtual adapters there is nothing in the code to choke the speed.