Proceedings 22nd International Conference on Distributed Computing Systems Workshops

The advancement of mobile telecommunication has made mobile commerce possible. Reliable communication between the retailers and the users is required for the provision of the services. Real-time property is also required for the marketing of the users' requirements and the provision of the local majority based services. Achieving assurance for these requirements under the evolving situation is required. Time distance, which changes with the situation is introduced as the efficient measure of the distance between the users and the retailers. The time distance oriented service system has been defined to satisfy real-time property and reliable communication in the local trade area. The system architecture, and the autonomous interactive communication between the users and the retailers are presented. Here, nodes have autonomy for fading unnecessary and inconvenient information through time distance based communication among them both for the marketing and provision. The nodes also autonomously reduce the information service area for achieving further effectiveness. It is shown that this architecture and technologies realize assurance for the real-time properties and reliability and achieve effectiveness in mobile commerce.

In the development of agent applications, interactions are an important issue, which must be faced with appropriate methodologies and tools. A separation of concerns between the agents and their interaction needs is helpful in the designing and the implementation phases of the life cycle. In this paper we propose XRole, a system that helps in dealing with interactions. It is based on the definition of roles, which are intended as intermediaries between the application needs and the environment needs. XRole is realized by exploiting the interesting features of the XML language. An application example shows the effectiveness of the approach.

With the expansion of mobility in communication technologies, the increasing individual audio solicitations require a definition of priorities in audio information. A new concept called superphony is identified which improves communication abilities by reconstructing an audio sphere around each user and filtering audio information based on user and environment profiles. Requirements and elements for an architecture are presented. Guaranteeing real-time audio stream management based on profiles in mobile contexts, without compromising security, are key issues. Several potential applications are also discussed.

Combining virtual reality and network multimedia techniques in applications is becoming popular. 3D geometry models are used in such applications. It is difficult to build mathematical models manually, but reverse engineering for building such models. Such a model is suitable for Internet transmission. However, there is still a bottleneck in using reverse engineering to reconstruct a relationship between vertices. The /spl alpha/-Shapes is an old method used for this purpose, and we propose methods to improve its efficiency. Our method can generate a compact model, and the average storage space required by our method is about half that of the original method. The advantage of our method is not the storage space but also reconstruction time.

There are many mapping schemes proposed in previous research on parallel proxy servers. The operations of these schemes are mainly URL-based, and therefore cannot fully benefit from the new persistent connection feature of HTTP/1.1. We propose a site-based mapping scheme that forwards all requests targeting on the same Web site to the same proxy server. The scheme then allows the proxy to use a single persistent connection to serve many client requests. The major advantage of the scheme is the reduction in the number of connection establishments. This reduction can save network bandwidth and reduce the user-experienced latency. Simulation results show that the proposed site-based scheme reduces 40%-70% of the connection setups and teardowns when compared to a traditional URL-based mapping scheme.

Composite events are required for many applications that require obtaining events from various sources, correlating them, and activating appropriate actions. One of the major issues in composite event system is scalability. This paper reports on a research that follows the situation concept of the Amit system, and proposes a parallel execution model for the event composition. The paper describes the model and its difficulties, and shows its usefulness using simulation results.

In this paper, we describe the development of our scene context dependent key frame selection method to reduce the amount of recorded video data. We propose the use of motion analysis (MA) to adapt to scene content in our key frame selection process. Based on the information generated by the motion analysis stage, frames in the video sequence which contain significant motion information are selected to retain for recording. We also show that our proposed method performs better than the traditional time-lapse recording method.

Lecture-on-demand (LOD) multimedia presentation technologies in networks are most often used in communication services. Examples of those applications include video-on demand, interactive TV and communication tools in a distance learning system, etc. In this paper, we describe how to present different multimedia objects on a Web-based presentation system. The distributed approach is based on an extended timed Petri net model. Using characterization of extended media streaming technologies, we developed a Web-based multimedia presentation system. For a real-world example, suppose a well-known teacher is giving a lecture/presentation to his students. Because of time constraints and other commitments, many students cannot attend the presentation. The main goal of our system is to provide a feasible method to record and represent a lecture/presentation. Using a browser with windows media services allows those students to view live video of the teacher giving his speech, along with synchronized images of his presentation slides and all the annotations/comments. In our experience, this approach is sufficient for distance learning environments.

We propose an efficient mechanism that is used to manage network with XML. It is an XML-based Dynamic network management system using Web. We describe a paradigm for the retrieval and presentation of management data using XML. It facilitates runtime agent extension and allows the MIB to be easily browsed and seamlessly integrated with online documentation. XML also allows the interchange of data between management systems. In this paper, we propose an XML-based Dynamic network management architecture using Web. The proposed architecture is implemented using Java and its push technology for the management of IP network.

In this paper the event concept is applied to support the interaction between mobile users and distributed location-aware systems. Taking a number of examples, the components of an event specification language are derived that can be used beyond the domain of location-aware systems.