What is a VLAN (part 3)

In our previous post, we configured a Qemu template for Windows NT.

With the NT template ready we will be prompted to give this project a name.

So I called this one ‘what-is-a-vlan’ sticking with the theme.

Now we can drag components out.  I selected the NT template that I’ve created, and dragged it out to the design pane.  Now we have a computer!

I then selected a simple Ethernet hub, to begin verifying that our configuration is working.  Just drag it out to the toplogy pane.

Now for the fun part, we are going to connect the Windows NT VM to the Hub.  Right click on the Qemu VM, and it’s available Ethernet interfaces will pop up.  It only has one, so select Ethernet 0.

Now you can select the Hub to complete the connection.  Hubs repeat every packet they receive, and don’t change anything.  They offer zero intelligence, and have no way to save you from yourself, if you do anything stupid (see creating a loop).  Every packet that comes into a hub is sent to every port going out.  They don’t care about protocols, or anything they just simply repeat.

 

So this will be our simple network.  The next thing to do is to turn on our PC, and install Windows NT 4.0.  I’ll save that for the next step which you can follow here.  If you don’t care about installing Windows, then you can skip to the following step where we will do a simple packet capture of the NT machine connected to the hub so we can observe how it’s packets look.

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