I chose to look at the NetKit network simulation tool first for two reasons: NetKit has an adequate number of lab scenarios ready to use and it is available as a bootable disk image, which makes it easy to just try it out. Because I wanted to keep things simple and avoid repartitioning my hard drive, I decided to run the NetKit disk image in a virtual machine on my PC.
So, I installed the free virtualization software, VirtualBox, on my Apple iMac. I downloaded the disk image from the NetKit web site and created a VirtualBox virtual machine to run the disk image. It all worked very well and it made me think about how virtual machines work on a host operating system.
All of the network simulation tools we have listed so far use virtualization to create a large number of guest virtual machines on a host operating system and then connect them together into a simulated network. Each tool uses a set of scripts and/or other software to simplify the process of creating and configuring the virtual machines and the creating the connections between virtual machines that create the simulated network.
People who are not familiar with virtualization will find the process of installing and setting up VirtualBox very educational. To use Netkit properly, they will have to attach the VirtualBox virtual machine to the same network that is connected to the host. machine. While this is not exactly the same as the processes used in the network simulation programs under consideration in this blog, the concepts are similar.
I expect that a detailed walk-through of the installation and setup procedure for a VirtualBox virtual machine would be a very good exercise that would teach a learner a lot about virtualization and networking between virtual machines and from virtual machines to hosts.
Also the fact that we are running a large number of Linux virtual machines inside a VirtualBox virtual machine on my host PC is fun to think about.