Lecture Notes in Computer Science s4

Adaptation of the Internet Product Information for Mobile Clients

Sangho Ha and Jungik Choi

School of Information Technology Engineering, Soonchunhyang University, Asan-si, Choongnam, 336-745, Korea {hsh,timing}@sch.ac.kr Tel: 82-41-530-1279, Fax: 82-41-530-1548

Abstract. With the advances of wireless technologies and mobile computing, m- commerce is being realized for many kinds of mobile devices. Service contents for m- commerce are usually newly written to meet specific characteristics of the target mobile devices, not exploiting contents currently served on the Internet for e-commerce. In this paper, we suggest a system to effectively exploit the Internet merchant information for mobile phones. We first design a merchant model for mobile phones, allowing for a friendly and concise view for the merchant information on the small screen. We then design and implement the system using XML and Java technologies. Finally, we give an experiment on the system.

Keywords: M-Commerce, Product Catalog, Mobile Clients, Mobile Phones, and XML

1. Introduction

Due to the advances of wireless technologies and the proliferation of Internet-enabled mobile devices, m-commerce is expected to enable within a few years. M-commerce[1] can be characterized as the emerging set of applications and services that people can access from their Internet-enabled mobile devices. Examples of m-commerce today are NTT DoCoMo’s i-Mode portal[2], Nordea’s WAP Solo Mobile Banking Service[3], Webraska’s SmartZone Platform[4], and so forth. M-commerce is being realized on several kinds of mobile devices such as PDAs, mobile phones, Smart phones, and so on. Service sites for m-commerce are usually designed to meet specific characteristics of the target mobile devices as in i-Mode. Therefore, mobile services could not be directly used for different mobile devices. Moreover, the mobile services are not compatible with the Internet services. However, we have a formidable amount of Internet contents which are currently served. If they are to be rewritten newly to meet mobile devices, the required works are formidably redundant, resulting in wasting a lot of resources. In this paper, we will suggest a system to effectively provide mobile clients with the Internet services currently provided for e-commerce. We are here focused on the merchant information and the type of mobile phone device. However, our system can be applied easily to other Internet services and different types of mobile devices. We also assume that products are written in XML[5]. However, we do not lose generality because we can drive the XML document from a given HTML document[6]. We first will design a product model of 3MP(Merchant Model for Mobile Phones), allowing a friendly and concise view about the merchant information on the small screen. This model is actually a compact version of the merchant catalog[7] designed for e-commerce, including only essential elements that clients are mainly interested in. We then will design a system to effectively exploit the Internet merchant information for mobile clients. The system includes two parts: the mobile web server and the mobile client. The mobile web server has a role of adapting the Internet merchant information for mobile clients using the 3MP model. This adaptation is done by transforming the Internet merchant information into the XML document conforming to the 3MP model. The mobile client parses and analyzes the document sent by the mobile web server, and provides clients with a friendly view about the product on the small screen of mobile phones. In section 2, we will design the 3MP model. In section 3, we will design a system to effectively exploit the Internet merchant information for mobile clients. In section 4, we will implement and experiment the system. Finally, we will remark conclusions in section 5.

2. A Merchant Model for Mobile Phones

We will suggest a new merchant model for mobile phones, called the 3MP model. The model is actually a compact version of the electronic catalog designed for e-commerce[7]. The only elements essential to mobile clients in the catalog are included in the 3MP model. For simplicity, we here do not consider the seller’s view such as mar- keting policies and the delivery information. However, the model can be expanded to include all kinds of elements required for m-commerce. We also preserve generality of the model so that it can be used for describing all kinds of products in the world. Figure 1. The 3MP model

Fig. 1 shows the overall structure of the 3MP model. In the model, the merchant information is described by the two elements: ClassIndent and ProductData. ClassIdent is used for classifying and differentiating merchants. Note that class is defined recur- sively, allowing the class information to be described hierarchically. ProductInfo con- tains the basic information, the selling information and the value added information. The basic information describes the details inherent to a given merchant such as Name, Image, ManuDate, Manufacturer, Specification, and Participant. The selling information describes all the information related to the merchant sale such as Price, and the value added information describes all kinds of information helpful to the con- sumer choice such as Evaluation.

3. The System Architecture

We will now suggest a system to effectively exploit the Internet service on mobile phones. The system includes two components: the mobile web sever and the mobile client module. The server has a role of bridging the gap in contents between e-commerce and m-commerce. That is, it adapts the Internet merchant information used in e-commerce to be also used in m-commerce. This adaptation is done by transforming the Internet merchant information into the document conforming to the 3MP model. The mobile client module parses and analyzes the document sent from the mobile web server, and provides clients with a friendly view about the document.

3.1 The Mobile Web Server

The mobile web server consists of six components as shown Fig. 2: the server manager, the DTD extractor, the XSLT retriever, the XSLT generator, the XSLT processor, and the XSLT document repository. We will describe these components in brief by explaining the process that the mobile web server handles a request given by a client. A request given by a client is sent to the server manager. It first interprets the request and retrieves the requested merchant information from the Internet shopping malls. We here assume that the retrieved information is represented in XML. The next work of the server manager is to transform the XML document to the form conforming to the 3MP model. The transformation is done by the XSLT processor[8]. It takes an XML document and an XSLT document as inputs, and transforms the XML document to another XML document according to the rule of the transformation specified in the XSLT document. The resulting XML document certainly will conform to the 3MP model because the XSLT document is constructed to do that. For generality, each Internet shopping mall is assumed to have its own format for describing products. Therefore, we need to have an XSLT document for each type of the merchant catalog. We take a policy to generate the XSLT document on demand. Once it is generated, it is kept in the XSLT document repository to be reused later for the same type of documents. The XSLT documents are generated using the XM- L2XML Mapper[9], which visualizes the two DTD, the source DTD and the target DTD, and map manually from the source DTD to the target DTD. When the source XML document coming from the Internet does not accompany its DTD, the DTD extractor derives the DTD using the XTRACT[10].

3.2 The Mobile Client Module

The mobile client module includes four components: the client manager, the XML parser, the information analyzer, and the mobile viewer. The client manager controls all the works requested by clients. It usually sends client’s requests to the mobile web server, and bypasses the XML document coming from the server to the XML parser. We here use the tree-based parser as the XML parser. The tree-based parser, also called the DOM parser, creates an internal tree, called the DOM tree, as a result of parsing the XML document. The DOM tree directly mirrors the hierarchical structure of the document. As such, the DOM parser is appropriate for our purpose because we should consider the whole data contained in the document.

Figure 2. The Mobile Web Server

It is important to provide mobile phone clients with a friendly view about the merchant information on the small screen. We provide views about the merchant information through four steps in sequence as in Figure 3. The first view is about a list of cat- egories of merchants. The second view is about a list of merchants, all of which be- long to the same category chosen by clients in the first view. The third view is about a list of elements of the information of the merchant chosen by clients in the second view. The final view is about the details of the specific element chosen by clients in the third view. Note that this view sequence reflects the structure of the 3MP model. To realize the four-step view about the merchant information, we designed a hierarchy of classes, which actually reflects the 3MP model. The information analyzer uses the DOM tree generated by the parser to construct the hierarchy of objects for the requested merchant catalog.

Figure 3. The Four-Step View of the Merchant Information

4. Implementation and Experiment

We implemented the system to exploit the Internet merchant information for mobile phone clients, which is suggested in this paper. In the system, the mobile web server was developed on the J2EE platform[11], and the mobile client module was developed on the J2ME platform[12]. We used the Xalan XSLT processor[13] in the mobile web server and the tree-based TinyXML parser[14] in the mobile client module. The TinyXML parser is a small-footprint Java-based XML parser, which is fitted on the J2ME MIDP devices such as mobile phones. To experiment on the system, we installed the mobile web server in the Windows 2000 server, and installed the mobile client module in the J2ME Wireless Toolkit for Windows[15], called J2ME WTK. We also installed the Jakarta-tomcat web server[16] in the Windows 2000 server for the Web interface. To experiment on the system, we wrote a sample XML document as an example of the Internet merchant information.

5. Conclusions

In this paper, we suggested a system to effectively exploit the Internet merchant contents served currently in e-commerce for mobile phone clients. We first designed a merchant model for mobile phones, the 3MP model, allowing for a friendly and concise view for the merchant information on the small screen. The model is so general that it can be used to describe all kinds of merchants in the world. Almost all of merchants in our world may be contents-oriented such as books, movies, and musical CDs, performance-oriented such as computers, automobiles, and electronics, or ap- pearance-oriented such as furniture, clothes, and shoes. All the merchants enumerated above were successfully represented by the 3MP model. We also developed the four-step view to provide mobile phone clients with the friendly and concise view about the merchant information on the small screen. The sequence of the views reflects the 3MP model. Our system was developed using XML and Java technologies, both of which are architecture neutral. As such, the system can be worked on any platform of mobile computing. Although we are focused on the merchant information and the mobile phone device in this paper, we believe that the system can be applied easily to exploit the other Internet services on the other mobile devices such as PDA.

References

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