Chapter 2 - Walkthrough
Maybe you've just taken the preliminary steps on installing Edubuntu, or perhaps you're just dreaming about when it will all be done. Whatever the case may be, let's take a walk through the completed Edubuntu lab to see how everything fits together.
The Edubuntu lab
Every Edubuntu lab consists of a room where people may come to use the facilities of the lab.
Ideally, the room is secured with a gate and burglar bars on the windows, and the really expensive components of the Edubuntu lab are locked away even further, in another room or in a cage. 
The room provides a comfortable space to work in, with desks at the right height for the learners at the school, and with enough plugs and cables for all the computers. All the users of the Edubuntu lab may sit down at any of the workstations and log in, to find their working environment just as they left it, even if they're using a different computer now.
The Edubuntu machines
An ideal Edubuntu lab usually contains between 20 and 25 workstation computers, although you may add workstations if you already have some computers, or if you can get donations. These workstations are connected to a server computer by way of a highspeed network.
The workstations are where the rubber hits the road, so to speak. They are standing out there on the desks, and everyone who uses Edubuntu is constantly using their keyboards and adjusting their screens, and so they do undergo some wear and tear. Because they are intended to be accessible to use, they are not that easy to secure. If something is locked away, it's hard to learn how to use it. To deal with this state of affairs, Edubuntu is designed so as to make the workstations as cheap and as easy as possible to replace. They should be completely interchangeable, and they store nothing: no documents, and no information about any user.
TODO: Add workstation pic here
An Edubuntu workstation
The server actually does all the work in Edubuntu. If the server goes away, the workstations will just stand around scratching their heads, like bees when something happens to the queen bee. Whatever you see when working at an Edubuntu workstation has been sent to the workstation by the server over the network. All the documents you save, and all the information regarding users, everything is stored on the server.
TODO: Add server pic here
An Edubuntu server
The third critical component of the Edubuntu lab is the computer network that connects all the machines in the room. If you're looking at a finished Edubuntu lab, the network cabling shouldn't be terribly obvious. However, every workstation has a Ethernet cable plugged into it, and you should be able to see the switch cabinet where all the cables go. However, if you were to look inside the trunking running along the walls or under the desks, you would see that there is an Ethernet cable for each and every workstation, connecting it to the network switch. The Edubuntu server is also connected to the switch by a flylead.
In this configuration, it is as if every workstation in the Edubuntu lab is connected directly to the server. The switch itself is transparent to the network. It sees to it that network traffic from the server is sent as directly as possible to the workstation for which it is intended. From the perspective of the computers, it looks as though they're all connected directly to each other.
If anything goes amiss in an Edubuntu lab, there's an even chance that it may be a problem with the network, since, from the workstation's point of view, a broken network is just as bad as a broken server. It can't do anything in either case.
 See Chapter 4 - Lab Layout