ABSTRACT
Mobile learning server is a platform to ordinary schools on which is possible to start mobile learning experiments. It includes SMS, MMS and Moodle environments. It has been developed to low cost use and mobile clients will be pupils own mobile phones or smart phones. Main tools in server are open source softwares Kannel and Mbuni. I have coded serves mobile learning environment onto Kannel and Mbuni and it is published with free GPL-lisence. I hope that there will be born open source community to develop this mobile learning server. I published in this paper some general design patterns of mobile learning server.
KEYWORDS
Open source, server technology, MMS, SMS, design patterns
1. design patterns
A design pattern “describes a problem which occurs over and over again in our environment, and then describes the core of the solution to that problem, in such a way that you can use this solution a million times over, without ever doing it the same way twice” (Alexander et al, 1977).
“The patterns are ordered, beginning with the very largest, for regions and towns, then working through neighbourhoods, clusters of buildings, buildings, rooms and alcoves, ending finally with details and constructions.This order, which is presented as a straight linear sequence, is essential for the way the language works” (Alexander et al. 1977).
There is hierarchical connectivity between the patterns on different levels. This connectivity relates all patterns in a sequence to each other building a semantic tree that represents a total structure.
Design patterns have the aim of externalizing knowledge to allow accumulation and generalization of solutions and to allow all members of a community or design group to participate in discussion relating to the design (Mor 2007).
The pattern description format used here contains the following fields (adapted from Avgeriou 2003):
a. Name – a unique name to distinguish the pattern and uniquely refer to it.
b. Problem – a brief description of the design problem at hand.
c. Motivation – an explanation of the origins of the problem, probably with an example for better communicating it. It may also contain the context of the particular problem if it is necessary in order to make it more comprehensible.
d. Solution – a description of the solution proposed by this pattern that addresses the problem and motivation stated earlier.
e. Known uses – examples of the pattern in real LMS. This is an important attribute of a pattern since it is claimed that a proposed pattern gets accepted by the corresponding pattern community, only if there have been two or three examples of its use by someone other than the one who suggested the pattern.
2. Mobile learning server
Mobile learning server (MLS) consists of two parts, server core platform (SCP) and mobile application platform (MAP). MLS is not important as itself. There is a lot of “technology toys”, which doesn’t change world of learning and it is possible, that MLS is one of them. MLS is however potentially important, because it makes possible to rapidly and easily to construct applications for mobile learning which together constitutes a mobile learning environment (MLE).
MLS relies on open source technology and open content. Server core platform and mobile application platform is build from existing and reliable open source components. First parts of MLE that I have constructed are also open source that I licensed with free GPL license. Exercises I created to mobile learning experiments are open content. I hope that there will be some day a community of software developers and teachers interested of mobile learning that will together develop MLE and its pedagogical use.
I have published specifications and exact building instructions of MLS in my blog vps.virtuaalikoulu.org/mls. With these instructions for example schools teacher of information technology or it-support person can build own server and teachers can begin to use MLE and develop own models of using mobile learning.
Hardware needed is an ordinary desktop computer (500 euros) with two hard drives and an ordinary mobile phone (100 euros) with SMS-capability connected to server with data cable. Server’s mobile phone is a gateway to GSM-network. MMS-messaging and mobile internet use needs that MLS is connected to public internet. That is why so much effort is used to get MLS to be a real production server with high security.
Use of MLS is cheap. Sending 1000 messages from server to pupil’s costs only 10 euros. MMS-messaging costs only data costs, because with MLS it is possible to send and receive MMS-messages without telecom firms MMS-servers. If in pupils phone is support to WLAN, use of MLE costs nothing in schools own WLAN or some open WLAN.
A teacher controls MLE by using WWW user interface, which I have coded. He or she can with user interface build from pieces SMS, MMS and email messages and sent these messages to students and students can answer to these messages. It is possible to collect students answer to WWW gallery and students can comment other students’ answers, such as photos and videos. Environment makes possible also building of simple learning games. Also collaborative learning is supported so that learners can in teams make for example problem solving exercises. Students can send messages to other students or group of students from mobile to mobile, from mobile to WWW and from WWW to mobile and from WWW to WWW. Students WWW user interface is of course possible to use via mobile Internet with GPRS, 3G or WLAN connection.
3. some design patterns for mobile learning server
SMS/MMS-games / MMS-blog
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WWW-server ———- Backup and security
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SMS-gateway / MMS-gateway
a. Name
WWW-server
b. Problem
How to build WWW-server for mobile learning environment?
c. Motivation
Most easy way to admin mobile learning environment and store data of environment is a WWW-server.
d. Solution
An ordinary Debian server is a good solution. Server can includes Apache HTTP-server with PHP & MySQL database support, proxy server, SSH server and email server. It is possible to install any Debian software packets needed for example WordPress, Mediawiki and Moodle.
e. Known uses
MobilED project : http://mobiled.uiah.fi/?p=37
a. Name
SMS/MMS-games
b. Problem
How to build interactive SMS/MMS- games?
c. Motivation
Many teachers and researches think that games can be effective tool in learning. Also mobile learning needs gaming solutions.
d. Solution
With SMS/MMS-gateway is it possible to build a connection between WWW-server and the phone network. With gateways configuration files we define sms-service like
group = sms-service
keyword = key1
get-url = “http://localhost/code/answer.php?sender=%p&to=%s&text=%r”
which calls script answer.php when to the gateway incomes message with keyword key1. Script answer.php gets as parameters students phone number, which identifies student, and students inputs to the game and with these inputs answer.php calculates response to the student.
a. Name
MMS-blog
b. Problem
How to build MMS-blog?
c. Motivation
With MMS-blog it is possible to collect student generated content to WWW-pages from for example nature and excursions to museums.
d. Solution
I installed Mbuni to my Debian Sarge Internet-server as MMSC and as VAS Gateway. When MMS-phone is configured to use my server as MMSC (it is possible to use many configurations, so it is easy to change to ordinary MMSC of phone operator) , MMS-messages goes from client to MMSC, from MMSC to VAS Gateway and from VAS Gateway to my MMS-blog. My MMS-blog is self coded PHP&MySql-script that puts parts of MMS-message to webpage. One row of table includes parts of one message: photo, text and video. Last column of row is a place for comments. All blog viewers can give some comments about message.
a. Name
SMS-gateway
b. Problem
How to build a SMS-gateway for mobile learning?
c. Motivation
SMS is very simple technology, but very popular and that’s why it is even nowadays useful for mobile learning and information systems. Every student has a mobile device, that supports SMS and they are experienced to use them. It has been used even in rural areas of Africa for mobile learning, so this technology is very equal in many senses.
d. Solution
Kannel is an open source WAP gateway. It attempts to provide this essential part of the WAP infrastructure freely to everyone. Kannel also works as an SMS gateway for GSM networks.
In mobile learning server Kannel can be used
1. to send SMS messages with GSM-phone connected to server with USB or serial cable
2. to receive and handle incoming SMS-messages for example in pedagogical games
2.with Mbuni to handle MMS with older phones
The first version on Kannel has published 2001 by WapIT Ltd. and the newest version 2006. My experience of Kannel is that it is fully reliable and speed of sending messages is good enough, about 6 messages per minute. Documentation is excellent and community of Kannel developers and users gives support actively.
e. Known uses
ULTRALAB:s project: http://www.formatex.org/micte2005/4.pdf
University Mobile Portal:
http://www.nano-world.org/nano/People/Martin.Guggisberg/wattinger2004_a.pdf
a. Name
MMS-gateway
b. Problem
How to build a MMS-gateway for mobile learning?
c. Motivation
The Multimedia Messaging Service (MMS) provides a rich set of content to users (pictures, audio, videos etc). It supports both sending and receiving of multimedia content by properly enabled client devices.
d. Solution
Mbuni is a Free/Open Source Multimedia Messaging Service (MMS) gateway. It includes both core network MMS switching capabilities as well as messaging gateway features, and is suitable for operators and MMS value added service providers.
First version of Mbuni published 2005 by Digital Solutions Ltd. The newest version is from year 2007.
e. Known uses
CoMobile-project:
http://www.emobility.unibe.ch/workshops/2006-10-
27/presentations/MobileTechnologies.ppt#266,21,MMS gateway – Mbuni
a. Name: Backup and security
b. Problem: How can mobile learning system prevent the loss of data after system failure? How to control risks of spam and viruses?
c. Motivation: Mobile learning systems contain important information in the form of student data,
course and information material. Possible system crashes can cause the loss of this information. Spam and viruses are reality also in mobile world.
d. . SCP replicates data among two hard drives (RAID) , takes backups to another server (rdiff), and has a software firewall (iptables) and an anti-spam tool (SpamAssasin) and anti-virus tool (ClamAV).
REFERENCES
Alexander, C., Silverstein, M. and Ishikawa, S. (1977) A Pattern Language: Towns,
Buildings, Construction (Center for Environmental Structure Series). New York,
NY: Oxford University Press.
P. Avgeriou, A. Papasalouros, S. Retalis, “Patterns For Designing Learning Management Systems”, European Pattern
Languages of Programming (EuroPLOP 2003) 25th–29th June 2003, Irsee, Germany.
Mor, Yishay and Winters, Niall (2007) Design approaches in technology enhanced learning. Interactive Learning
Environments (15)1:61-75. Taylor & Francis.
Kannel, 2008. www.kannel.orgMbuni., 2008. www.mbuni.org
