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Page 1: Mobile eLearning System Employing a Jini-Agentelearningap.com/eLAP2007/.../P37eLearningAP_MobileeLearningSystem.pdf · The mobile eLearning system employing a Jini-agent Sang Tae

Mobile eLearning System Employing a Jini-Agent

Fourth International Conference on eLearning for Knowledge-Based Society, November 18-19, 2007, Bangkok, Thailand

37.1

Mobile eLearning System Employing a Jini-Agent

Sang Tae Kim, Asif Iqbal, Byoung-Ju Yun, Jonghun Baek, and Hyun Deok Kim

School of Electrical Engineering and Computer Science Kyungpook National University

South Korea [email protected]

Abstract A mobile eLearning system employing a

Jini-agent technology has been proposed and demonstrated to realize anywhere, anytime and anyone learning. It enables the users to utilize the eLearning system through a resource-limited mobile device without any client program installation in it. It also automatically finds and provides the users the lists of the services and contents available on various networks. The proposed eLearning system can realize a seamless eLearning service over wired and wireless networks.

1. Introduction

The mobile eLearning system using

portable devices such as portable digital assistants (PDAs), smart phones and portable multimedia players (PMPs) can realize “anywhere, anytime” learning. Furthermore, since most of peoples own mobile devices anyone can easily utilize the eLearning system by using various mobile devices.

To realize the mobile eLearning system, the mobile device should interact with other electronic devices such as servers, desktop personal computers (PCs) and peripheral devices such as printer and scanner. Since the mobile device and the other electronic

devices are usually implemented based on different operating systems and platforms depending on the manufacturers, it is difficult to realize the interoperation between the devices. Thus the middleware plays a key role to provide the interoperation between the devices with different platforms.

Especially, the Jini is one of the widely used middlewares and provides the plug and play operation, which is essential to the users not familiar to the electronic devices. It also provides a seamless interoperation between the devices with different platforms. However, the Jini technology can not be applied directly to the mobile devices since the resources of the mobile devices such as the processing power and the storage size are not sufficient to support a Java virtual machine (JVM).

In this paper, we propose and demonstrate a novel mobile eLearning system by using a Jini-agent. Two exemplary eLearning services are demonstrated by using the Jini-agent and PDAs. One is the file transfer from a client mobile device to a server and the other is the remote submission of the assignment in the form of a printed paper. We demonstrate that the user of the mobile device can submit the assignment by printing it using the printer located at the teacher’s side without printer driver installation in mobile device.

Page 2: Mobile eLearning System Employing a Jini-Agentelearningap.com/eLAP2007/.../P37eLearningAP_MobileeLearningSystem.pdf · The mobile eLearning system employing a Jini-agent Sang Tae

Sang Tae Kim, Asif Iqbal, Byoung-Ju Yun, Jonghun Baek, and Hyun Deok Kim

Special Issue of the International Journal of the Computer, the Internet and Management, Vol.15 No. SP3, November, 2007

37.2

2. The Jini Technology By providing a fast and easy way for

clients to locate available services, the Jini technology simplifies interactions over a network. When we use the Jini technology, no additional reconfiguration is required by the user and system administration will be simplified. With the Jini technology's commanding service discovery mechanisms, the clients can utilize a particular service without having any foreknowledge of its implementation.

As a distributed computing architecture, the Jini technology also eases implementation details. The Jini technology simplifies the task of writing distributed applications and other services for the network. Powerful helper utilities assist with service and client development by encapsulating common functionality related to service discovery, lease management, and maintaining a service’s registration in the Jini technology-enabled lookup services. Additional design flexibility is provided by the Jini technology’s superior capabilities for moving objects around the network, making wire protocols a transparent implementation detail.

The Jini architecture can enable an entire industry to seamlessly integrate fragmented information systems into one easily accessible network is shown in Fig. 1. It consists of an infrastructure and programming model that addresses the fundamental issues of how clients and services discover and connect with each other to form an impromptu community. Written entirely in the Java language and utilizing its object-oriented features, the Jini technology uses the mechanisms pioneered by the Java Remote Method Invocation API to move objects around the network [1].

Jini Technology

Operating System

Network Transport

Application Service

Java Technology

Jini Technology

Operating System

Network Transport

Application Service

Java Technology

Figure 1. The Jini architecture The Jini technology is originally

developed for a desktop environment and implemented by using a Java virtual machine (JVM). Namely, it can not be applied directly to the mobile eLearning system since the resources of the mobile devices such as the processing power and the storage space are not sufficient to support the JVM in the mobile devices. Though we can develop mobile devices supporting the JVM, however, they will be unreasonably expensive or bulky. Thus, it is important to develop an agent which enables the mobile device to participate in the Jini network even when the resources of the devices are insufficient [2].

3. The Mobile eLearning System

Today's web browsers are increasingly

used in various devices such as workstation, personal computer (PC) and mobile device. Thus we have implemented the Jini-agent system based on a web browser, which will facilitate the users to utilize the Jini network services by using a user-friendly web browser of the mobile device. The configuration of the Jini-agent system and the mobile device are shown in Fig. 2.

Page 3: Mobile eLearning System Employing a Jini-Agentelearningap.com/eLAP2007/.../P37eLearningAP_MobileeLearningSystem.pdf · The mobile eLearning system employing a Jini-agent Sang Tae

Mobile eLearning System Employing a Jini-Agent

Fourth International Conference on eLearning for Knowledge-Based Society, November 18-19, 2007, Bangkok, Thailand

37.3

KVM

HTTP engine

Embedded operating system

HTML documentcreator

Form parser

Device specific application

HTML parser

Servlet engineHTTP engine

Jini technology

Native operating system

Java applet

Application

InternetMobile device

Jini-agent system

Figure 2. Configurations of the mobile eLearning system employing a Jini-agent

The Jini-agent system has the JVM to

execute the Servlet engine on which the Java applet is executed. Since the Java applet is executed in the agent system can participate in the Jini network and utilize the Jini network services. The agent system also has a HTTP engine and HTTP parser to support a web-based service.

The mobile device has been implemented by using the KVM which is widely used in mobile devices to support Java environments. The mobile device has a HTTP engine and a HTML document creator to support a web browser. The web browser

of the mobile device is used to access the Jini-agent system by using a HTTP protocol. If the mobile device is accessed to the agent system, Java applet of the agent system is downloaded to the mobile devices. Thus, the users can access the Servlet engine of the agent system through the web browser of the mobile device.

The Form parser of the mobile device converts the Java message transmitted from the agent system to a proper one readable via the HTML. The connection between the Jini-agent system and the mobile devices is established by using a TCP/IP interface. Other devices are also connected to the Jini-agent system through the TCP/IP interface.

4. Experimental Results

To evaluate the validity of the proposed

mobile eLearning system, we implemented a Jini-agent system and a client mobile device and. The configuration of the mobile eLearning system is shown in Fig. 3.

We used a KVM and a CLDC on the mobile device and the operating system of the PDA was Microsoft Windows for Consumer Electronics (CE). The user interface of the mobile device was implemented by using a Java applet and the web server of the Jini-agent system was implemented by using a Servlet, which enabled the client to participate in the Jini network through the web browser [3].

AP

LAN

Device 1

Device 2Jini-agent

system

Client

e-learning Server

AP

LAN

Device 1

Device 2Jini-agent

system

Client

e-learning Server

Figure 3. The mobile eLearning system employing a Jini-agent

Page 4: Mobile eLearning System Employing a Jini-Agentelearningap.com/eLAP2007/.../P37eLearningAP_MobileeLearningSystem.pdf · The mobile eLearning system employing a Jini-agent Sang Tae

Sang Tae Kim, Asif Iqbal, Byoung-Ju Yun, Jonghun Baek, and Hyun Deok Kim

Special Issue of the International Journal of the Computer, the Internet and Management, Vol.15 No. SP3, November, 2007

37.4

The Jini-agent system was implemented to provide a service list available to the client and thus the users can easily search the services available in the Jini network. The servlet of the web-based agent system receives the proxy ID and the service ID of the specific service registered to the Jini network from the Jini Lookup Service. The servlet lists up the available service list form the proxy ID and the service ID and provides the service list available to the mobile device

The process of the service list provision is as follows. The constructor of the service list initializes the user interface and sets up all the objects required for the client to participate in the Jini network. It also creates a Discoverer, which tries to discover the services available through a DiscoveryListener on a LookupDiscovery instance[4]. An example of the service list of the mobile device (client) is shown in Fig. 4.

Figure 4. The service list of the mobile e-

learning system We have demonstrated that a file

download service and a printing service. The selection process of the file to be downloaded from the file server on the Jini network is shown in Fig. 5(a) and the downloading process is shown in Fig. 5(b).

If the user selects a file server from the service list through the web browser of the client, the client sends the proxy ID and the service ID of the file server to the Jini-agent system. The agent system searches the file server and informs the client of the usability

of the file server. After receiving the message, the client accesses the file server and the user can download files in the file server. Since the Java applet is downloaded from the Jini-agent system the user can download the file by executing the Java applet through a web browser. Thus there is no need to install the Java applet in the mobile device, which makes it possible to utilize a Jini network service with a resource-limited mobile device.

Figure 5. File download service: (a) a file

search and (b) a file download After reading a downloaded file (test.txt),

we have the file to be printed by using another service provider (a printer). The file selection process to be printed and the print process are shown in Fig. 6 (a) and (b), respectively. If the user execute the printing service through the web browser of the mobile device, the client sends the proxy ID and the service ID of the printer to the Jini-agent system. The agent system searches the printer and informs the client of the usability of the printer. After receiving the message, the client transmits data to the printer to execute a file printing. When the file printing service has been completed the printer server sends a message to the Jini Lookup service to inform the client has completed the use of the service. It is notable that there is no need to install any printer driver in the client to use a file printing service.

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Mobile eLearning System Employing a Jini-Agent

Fourth International Conference on eLearning for Knowledge-Based Society, November 18-19, 2007, Bangkok, Thailand

37.5

Figure 6. Printing service: (a) a file search

and (b) a file print 5. Conclusion

We have demonstrated a Jini-agent-

based mobile eLearning system. The Jini-agent is composed of a Lookup server and Servlet engine and implemented on PC. It enables the users to utilize the eLearning system through a resource-limited mobile device without any client program installation. It also automatically finds the list of the available services and contents when the mobile device is connected to the eLearning system. The Jini-agent system overcomes the security problem of the conventional web-based eLearning system though it uses the web browser as a user interface since we included an advanced security policy based on Java security model.

Acknowledgement

This work was partially supported by the Mobile Technology Commercialization Center (MTCC) and the Brain Korea 21(BK21) Project. References

1. Sun Microsystems (2001). Jini

Networks Technology 2. Sang Tae Kim., Hyund Deok Kim.

Interoperation of Home and Mobile Network Devices Employing a Jini-Agent System.

3. Landis, S., and Vasudevan, V. (2002). Reaching out to the cell phone with Jini. System Sciences

4. Sing, Li. (2000). Professional Jini. Wrox Press Ltd

5. Gupta, R., Talwar, S., and Agrawal, D.P. (2002). “Jini home networking: a step toward pervasive computing”. IEEE

6. Sun Microsystems (1998). Java Object Serialization

7. Sun Microsystems (2002). Java2 Platform Micro Edition.

http://java.sun.com/j2me/index.jsp