Monday, December 10th, 2007
Probably one of the most used applications on the Internet for retrieving information - search engines - are quite a challenge for asynchronous access.
For people with permanent broadband access, that might sound quite bizarre - who really wants to wait hours or even days for the result of one single request? But- with no permanent connection at all this is still better than nothing, it is one way to do real research and explore - not just receive pre-packed information at regular intervals.
There was even an initiative to tackle these desires. TEK - which stands for Time Equals Knowledge, is a special search engine developed for the use with extremely limited bandwidth or non-permanent connections. This looks like a perfect match for the asynchronous school-server search-concept.
After trying it out, I was quite disappointed, though. The Linux version of the client is quite outdated already and the whole concept just seems to be much too complicated. All results are transferred by email - which means one has to log-in into his email account, open the attached files every time he wants to see a result or post a new request. Also, the search results I got were not quite appropriate - nothing you would find typing the same request into Google.
Therefore I am currently investing the possibility of providing an easy, lightweight application for Internet search, were all requests and the results are immediately visible for all clients - without logging in or anything. A custom build web application on the school-server provides a simple search form as well as the history of all completed and pending requests.
The proxy server wwwoffle is used as the back-end system to save the requests which are then transferred to the Internet via the mobile server. This makes it possible to use any search engine on the net and retrieve the same results.
wwwoffle then processes the requests which can look like: http//:www.google.com?q=Schoolserver
As wwwoffle is able to automatically follow links it is possible not only to save the result list, but also the first ~10-15 linked pages. These will be transferred back to the school-server and will be listed as completed requests, fully browsable and accessible for everyone.
Monday, November 19th, 2007
Today I’d like to introduce a few projects with similar approaches to providing asynchronous connectivity in challenged environments, which all served as an inspiration for the layout of the my school server connectivity project.
- Firstmilesolutions / United Villages
Evolved out of a MIT spinoff in This is probably the pioneering project using store and forward concepts in addition with WiFi - Vehicles. Operating in India and Cambodia they are adressing mostly commercial needs of the local community.
http://www.firstmilesolutions.com/
- Kiosk Net (University of Waterloo)
A quite sophisticated approach to provide End-to End Connectivity to rural internet kiosks. They use a new overlay bundle protocol for adding delay tolerant and their own Routing protocol for communication between kiosks and the internet. Focus on providing safe and secure communication.
http://blizzard.cs.uwaterloo.ca/tetherless/index.php/KioskNet
- Wizzy Digital Courier
Wizzy Digital Courier is a South african initative providing access to schools - a very similar target audience to the OLPC school server project.
For saving phone charges charges, a system of locally available web content is provided with synchronization over delayed Dial Up at night. For schools without phone access they use USB Storage Divices to carry data to and from the schools.
http://www.wizzy.org.za/
Though the nature of my project, which is to provide free access to communication and information for education, partly differs from these initiatives, many concepts and experiences can be used to build a specifically designed system for the school server.
Saturday, November 10th, 2007
No posts for a long time…spent the time doing research on similar projects and suitable software.
I am convinced that the sucess of the entire systems greatly depends on the design and ease of use of the underlying software, not so much on the perfect technical solution.
The schoolserver’s focus is on providing access for educational content, in contrast to pioneering work of the DakNet project which is geared more towards commercial use.
1. Which kind of content and which applications make sense for the target audience?
Polls in higly developed countries (e.g. Germany Youth Institute) show what applications are used in education. Teacher working with the pre-highschool age group (similar to the intended target audience for the XO) used the internet:
- to do own research for their instruction
- to work with the kids on researching a specific topic
- to practice reading with online text
- to copy websites and work with the texts offline
- about 20% introduce email
- another 20 % work with the pupils on publishing own information
- about 10% use chat and other real time communications
It is obvious that all real-time communications like chat, VoIP or virtual online communities like Second life are impossible to use with an asynchronous system as they depend on direct user interaction with the server. Still with these restrictions I can identify 5 main groups of educationally sensible applications that can be implemented in some way to be used without direct connection to the Internet.
- Encyclopedias or other generally accepted information (e.g. Wikipedia)
- Always updated information (e.g. Online Newspapers, -Magazines, Blogs, other subscriptions of relevant web sites)
- Search engine
- Possibility to publish own information (Own website, Blog)
- Email
2. What are the specific requirements for these applications?
First and foremost they must be easy to use. Sophisticated user management or endless configuration possibilities won’t do any good.
I am currently researching what central features each of these 5 applications should possess and how to implement these features with the help of available open source software.
My goal is to provide a portal on the school-server with easy and direct access to all applications and content over web-browser.
Friday, October 5th, 2007
Here’s a brief outline the project “Asynchronous Internet Access for OLPC school servers”and what questions I am about to tackle ..still subject to change:
- Background and Challenge
- Poor IT infrastructure hinders development and access to information society
- OLPC Projects offers learning tools but not connectivity
- Discussion of alternatives: Sneakernet, VSAT, GSM, dial-up
- Assumption: A system based on a mobile servers acting as a “digital postman” synchronising data between schools and cities with Internet connection is a feasible solution
- Content and didactic requirements
- What potential does Internet in developing countries offer for education?
- Which types of content/applications can be successfully introduced in class?
- What restrictions (due to the delay) must be considered ?
- Technical Requirements
- What kind of additional hardware is needed?
- Requirements of the Mobile Server and Internet Hub
- How are connections established ?
- Routing, Wifi-coverage, Speed, Security
- Software and Usability
- Which kind of software is to be used to provide email, offline browsing, research etc.. ?
- Ease of use: connection establishment, synchronization, fetching etc..?
- Rights management: Who decides which content to fetch?
- How do clients (e.g. the XO Laptop) access stored content on the server?
Tuesday, September 25th, 2007
For development and testing I built up a scenario with the 3 necessary components for testing at home.
- The School Server: A middle-class consumer PC 2,8 Ghz Intel Processor, 1024 MB of Ram, 80 GB Hard Drive running on the latest school server software XS OS 128
- The mobile Server: A 4 year old IBM Think Pad Laptop, Centrino Processor, 1024 MB Ram 80 GB Hard Drive running on Fedora 7
- The internet access point: A regular 802.11 b/g wifi Router
All in all a quite realistic layout I would say. All similar consumer/ second hand (e.g. cheap) hardware is fine to to the job.
The trickiest part was to get a working wireless connection from school-server to mobile-server (the laptop)
Ad-Hoc Wifi connections are not the easiest thing to set up under a Linux environment. Drivers are not available for all wireless chipsets, are sometimes buggy or won’t work in Ad-Hoc Mode.
After some research I decided to use wifi cards based on the RT61 chipset as they provide native Linux drivers. One 802.11b/g PCI-Card for the school-server and a pcmcia version for the mobile-server.
Linux installation files for both cards can be found here.
Installation is quite straightforward except for one thing. On Linux kernel 2.6.22 (which the school server OS runs on) the
pci_module_init is deprecated and so the installation source won’t compile correctly.
The fix:
in the module rtmp_main.c ,
look for
return pci_module_init(&rt61_driver);
and replace it with:
return pci_register_driver(&rt61_driver);
before compiling the source code.
So, my “workbench” is ready now. I can transfer files from access point to mobile server and from mobile server to school-server. Wireless.
Saturday, September 22nd, 2007
The folks at OLPC are not only developing the XO Laptops and the child-friendly designed OS Sugar
A server software based on Fedora 7 is also being developed for the use at schools and as a gateway to the Internet.
The latest server software can be found here.
As the server is planned to be administrated via web-interface, it naturally doesn’t come with a GUI, but for everyone who wants to develop, test, or just play around with the OS more comfortably, here’s a quick HOW TO:
You need to download the X Window System, and a Desktop Environment which can be KDM, or as in this case GNOME:
yum groupinstall "GNOME Desktop Environment"
yum groupinstall "X Window System"
For usual graphic adapters this should do, after login just start the Gnome Desktop Manager with
gdm
and you have a running GUI for your OLPC School Server.
Saturday, September 22nd, 2007
First things first. Before going on to content, distribution and software issues, the basic connections between internet hub, Mobile Server and OLPC school server must be set up.
The “OLPC school server“, designed for about 100 pupils is currently a a off-the-shelf product which can be configured according to the school’s needs. The specific feature is the wireless mesh interface with Active Antennas to connect the Server with the laptops.
Some configuration suggestions from the OLPC team can be found here http://wiki.laptop.org/go/XS_Server_Specification#XS_Specifications.
Production will not likely start before next spring.
Now, how am I going to connect the school server and vehicle server (like explained in How it should work) ?
Keeping in mind that…
- it must be easy to set up / install
- it must be easy to connect
- Costs need to be kept low. Really low.
…the first and most obvious idea was that a wifi-capable laptop as the server in the vehicle logs into the wireless mesh network of the school.
I decided against that for some reasons.
- configuration issues: the mesh networks at the schools are specifically designed for the XO Laptops - could cause problems
- hardware problems: regular wifi-hardware isn’t capable of logging into mesh networks
- speed
I suggest to build in an additional 802.11 b/g pci-wifi-card which is independent from the mesh and can build ad-hoc wifi connections with the mobile server.
Costs should not be a big problem here, these cards come for as low as 15 EUR
Friday, September 21st, 2007
If this is your first visit and you want to get an overview what this is all about, please have a look through following pages, which are also accessible on the right navigation bar:
I am going to post regularly on this project, so it is worth checking out the site from time to time.
Your opinion is important to me, please feel free to comment, ask questions, and criticise !
