Yesterday we used this network in anger.
Installed Greenfoot on the LTSP server. (Greenfoot is a kind of "skin" that runs on the Java Development Kit, it's kind of Scratch like in that you have visual characters / sprites, but introduces OOP as each character in an instance of an object. There is a code-behind for each character which is written in pure Java with some extra Greenfoot API's that do things like "move forward" etc. - this is written to work with the JDK but seems to work perfectly well using the ODK)
In the foreground you can see 4 workstations. Each has a r-pi connected to a DVI monitor, mouse, keyboard via the 2 USB ports. Each is connected to an 8 port gigabit network switch via a patch cable (you can just see that , little grey box at the end of each row)
"My" network is made up of the blue cable you can see running up along the walls and along the trunking and up into the ceiling. This is alongside but separate to the windows network that is provided by RM corporation.
Each row is currently connected to a 16 port 100 MBs switch which is on the shelf on the wall at the front of the room, connected to eth0 on the server. (I accidentally bought a 100MBS switch instead of 1000MBS so currently I have a bottle neck)
The LTSP server is then connected via a single RJ45 link to my firewall/router, DNS/DHCP and Kerberos/LDAP server which are in my office.
22 out of 30 students logged in fine, 2 of the rows of 4 seemed to have no connectivity (the port light on the switch that goes up to the big switch was blinking constantly)
The system, constarined as it was to 100 MBS was very laggy but useable.
To try to improve the situation I am installing an eight core processor to replace the single core processor and I am splitting the single 30 client subnet for the LTSP clients in the classroom into two 15 client sub-nets. (By installing a third NIC in the LTSP server, and configuring the LTSP DHCP) I will then use two gigabit 8 port switches at the server end, on the shelf at the front to provide links to each 15 client subnet on either side of the classroom)
edit - also wanted to mention berryboot can also boot the r-pi's into standard Raspbian but I am having trouble configuring this to mount the user home directory and take authentication from the Kerberos/LDAP server at present.