We recently held a olpc / LTSP presentation in Vienna, which gave us the opportunity to be experimental and check the wonderful world of using Sugar on various platforms via LTSP. We hooked up 2 Acer Aspire One netbooks, a Thin Client (Artec), a laptop acting as LTSP and ejabberd server, along with 2 traditional XOs.
Before going into the details of the experiment some explanation is due. LTSP stands for Linux Terminal Server Project, and refers to the use of a mainframe like infrastructure, where minimal systems without hardrives and little CPU and RAM can be used as diskless terminals.
The idea is that everything runs from the server, with the client netbooting the environment and using the little RAM and CPU it has to load the kernel and connect its display session to the server.
Usually older computers (Pentium 200hz+ with 64 MB RAM) are re-used in this way, though there are various dedicated thin terminals that are mobile phone sized and are highly energy efficient. LTSP terminals usually have no moving parts, making them hard to break.
Whereas the XO, and rightly so, has been marketed as the guerrilla educational device for the 3rd world, it is a little tied in with a specific company and a specific set of hardware. Sugar on the other hand is not, and in my view the more hardware can run sugar natively and flawlessly, the closer we get to a solution that can really feed the masses.
As the politics of OLPC grow and change, such as dropping Sugar support, or moving to Windows (these are just speculations), Sugar's growth and deployment should not be affected. If anything it gives Sugar and Sugar Labs a firm grounding its its ability to run on multiple systems and scenarios.
In our presentation case, for a mobile server, we used a dual core 1.8ghz with 2 gigs of RAM. Setting up the server on the laptop was pretty straight forward, and involved installing LTSP on top of a base Ubuntu system, and then adding Sugar sessions for all newly created users.
One can choose other sessions of course, but our interest was to test collaboration on all the machines, in which case Sugar was our environment of choice, and the login session for all our users. Installing ejabberd on the ltsp server was the only requirement for sharing across all machines. I followed the instructions as layed out on the laptop.org wikipedia and nubae.com site.
There are still some issues installing ejabberd, such as permissions of the /etc directory, but it has generally become much simpler to install for anyone. Without ejabberd the machines did see each other via xmpp-local, including seeing shared activities, but they tended to fall of the network neighborhood. With ejabberd the machines were visible continuously and were very responsive to connections.
For testing purposes we tried sharing chat across all the machines, which worked flawlessly. The applications in general seemed to load much faster than with the xo hardware, both on the thin can and the acer ones. It was nice to see that a dual core laptop with 2 gigs of ram was more than happy to serve 6 thin terminals at once. This makes the perfect mobile school, with all the machinery fitting into one backpack!
The laptop server was set up to get wireless internet, and then hand out LTSP through the wired interface, using a gigabit switch as a connector. One of the things that still requires a lot of work, and perhaps this is due to using Ubuntu, is getting all the activities to work.
I tested various activities like puzzle slider and jigsaw puzzle, which just left the activity icon cursor flashing on the screen and eventually fell back to the main screen. Another problem was that turning off or restarting the session was nonreactive.
Also many, of the items in the control panel either crashed sugar out completely (date/time) or didn't work. These problems have recently been turned into bug reports, so we hope by the next release of Ubuntu, the environment works as it should.
LTSP and sugar are a great combination and much wished for in schools in the developing and developed world. We will talk a little more about the advantages of LTSP, Sugar and scaling using LTSP-Cluster, as well as wireless LTSP and Fat clients in another article.
David van Assche is an education technologist, helping to implement both pedagogical solutions for IT, and migrating systems from Windows to Linux. You can find his blog at nubae.com