Given the undeniable popularity of the Web, providing efficient and secure access to remote databases using a Web browser is crucial for the emerging cooperative information systems and applications. In this paper, we evaluate all currently available Java-based approaches that support persistent connections between Web clients and database servers. These approaches include Java applets, Java Sockets, Servlets, Remote Method Invocation, CORBA, and mobile agents technology. Our comparison is along the dimensions of performance and programmability. Our findings point out that best performance is not always achievable with high programmability and low resource requirements. Moreover, the mobile agent technology needs to improve its programmability while giving particular emphasis on its infrastructure.

The popularity of the Web as a universal access mechanism for network information has created the need for developing Web-based DBMS client/server applications. However, the current commercial applet-based approaches for accessing database systems offer limited flexibility, scalability, and robustness. We propose a new framework for Web-based distributed access to database systems based on Java-based mobile agents. The framework supports lightweight, portable, and autonomous clients as well as operation on slow or expensive networks. The implementation of the framework using the aglet workbench shows that its performance is comparable to, and in some case outperforms, the current approach. In fact, in wireless and dial-up environments and for average size transactions, a client/agent/server adaptation of the framework provides a performance improvement of approximately a factor of ten. For the fixed network, the gains are about 40 percent and 30 percent, respectively. We expect our framework to perform even better when deployed using different implementation platforms as indicated by our preliminary results from an implementation based on Voyager.

The popularity of the Web as a universal access mechanism for network information has created the need for developing Web based DBMS client/server applications. However, the current commercial applet based methodologies for accessing database systems offer limited flexibility, scalability and robustness. We propose a new framework for Web based distributed access to database systems based on Java based mobile agents. The framework supports lightweight, portable and autonomous clients as well as operation on slow or expensive networks. The implementation of the framework shows that its performance is comparable to, and in some cases outperforms, the current approach. In fact, in wireless and dial-up environments and for average size transactions, a client/agent/server adaptation of the framework provides a performance improvement of approximately a factor of ten. For the fixed network, the gains are about 40% and 30% respectively.