Java-based Mobile Agent System Research Articles

Bio-Inspired Deployment of Software over Distributed Systems

This paper presents a middleware system for multi-agents on a distributed system as a general test-bed for bio-inspired approaches. The middleware is unique to other approaches, including distributed object systems, because it can maintain and migrate a dynamic federation of multiple agents on different computers. It enables each agent to explicitly define its own deployment policy as a relocation between the agent and another agent. This paper describes a prototype implementation of the middleware built on a Java-based mobile agent system and its practical applications that illustrates the utility and effectiveness of the approach in real distributed systems.

Achieving Mobile Agent Systems interoperability through software layering

Interoperability is a key issue for a wider adoption of mobile agent systems (MASs) in heterogeneous and open distributed environments where agents, in order to fulfill their tasks, must interact with non-homogeneous agents and traverse different agent platforms to access remote resources. To date, while several approaches have been proposed to deal with different aspects of MAS interoperability, they all lack the necessary flexibility to provide an adequate degree of interoperability among the currently available MASs. In this paper, we propose an application-level approach grounded in the software layering concept, which enables execution, migration and communication interoperability between Java-based mobile agent systems, thus overcoming major setbacks affecting the other approaches currently proposed for supporting MAS interoperability. In particular, we define a Java-based framework, named JIMAF, which relies on an event-driven, proxy-based mobile agent model and supports interoperable mobile agents which can be easily coded and adapted to existing MASs without any modifications of the MAS infrastructures. Results from the performance evaluation of MAS interoperability was carried by using JIMAF atop Aglets, Ajanta, Grasshopper, and Voyager, demonstrating that the high-level JIMAF approach offers high efficacy while maintaining overhead at acceptable levels for target computing environments.

A location model for smart environments

This paper presents a location model for location-aware and user-aware services in smart environments. It can be dynamically organized like a tree based on geographical containment, such as that in a user–room–floor–building hierarchy and each node in the tree can be constructed as an executable software component. The model is unique in existing approaches because it enables location-aware services to be managed without any database servers, it can be managed by multiple computers, and it can provide a unified view of the locations of not only physical entities and spaces, including users and objects, but also computing devices and services. A prototype implementation of this approach was constructed on a Java-based mobile agent system. This paper presents the rationale, design, implementation, and applications of the prototype system.

A Spatial Model for Ubiquitous Computing Services

We present a world model for location-aware and user-aware services in ubiquitous computing environments. It can be dynamically organized like a tree based on geographical containment, such as in a user-room-floor-building hierarchy and each node in the tree can be constructed as an executable software component. The model is unique to existing approaches because it enables location-aware services to be managed without databases, can be managed by multiple computers, and provides a unified view of the locations of not only physical entities and spaces, including users and objects, but also computing devices and services. A prototype implementation of this approach was constructed on a Java-based mobile agent system. This paper presents the rationale, design, implementation, and applications of the prototype system.

Building reusable mobile agents for network management

Mobile agents can migrate among nodes to perform a set of management tasks at each of the visited nodes. Existing mobile agent-based network management systems often assume that their mobile agents are designed to work in particular networks to raise the efficiency of agent migration among multiple nodes. Unfortunately, such mobile agents cannot be reused in different networks. This paper proposes a framework where a mobile agent for network management is composed of two kinds of software components, an itinerary part and a behavioral logic part. Both components are implemented as mobile agents. The former is a carrier designed for particular networks, and it can efficiently navigate other mobile agents among nodes in its target network. The latter defines management tasks performed at each node independently of any local network. This framework allows a mobile agent for network management to be reused in various networks without being modified. A prototype implementation of this framework and its application were built on a Java-based mobile agent system.

Special issue: Research in ad hoc networking, smart sensing, and pervasive computing

Wireless communications have added a new dimension to the networking field. One recent development is the wireless ad hoc network, which is characterized by many mobile computers interconnected by wireless transceivers without the support of fixed infrastructure, making it attractive for use in emergency relief and battlefield communication. The network can be formed quickly and dynamically. However, efficiency of ad hoc networks needs to be addressed carefully. For example, power saving is a critical issue to extend the lifetime of an ad hoc network. The medium access control (MAC) is also a very challenging issue since interference would be intensive in an ad hoc network. Mobility management and QoS are important to support high-level applications. Sensor networks, which are created by tiny smart sensors combined with computation and communication capabilities, are being proposed recently for applications such as military combat, environment surveillance, and pollution detection. Common features of sensor networks and ad hoc networks include multi-hop communication and dynamically changing network topology. These two new network architectures, together with the development of lightweight, small computing devices, have made pervasive computing possible. Many issues, such as routing, medium access, energy management, fault tolerance, and scalability, need to be addressed. This special issue is targeted at addressing the development of these issues. Nine papers are selected for publication in this special issue from over thirty submissions. The first paper ‘Spatial Agents: integrating of user mobility and program mobility in ubiquitous computing environments’ by I. Satoh presents a framework for the building of context-aware applications in ubiquitous and mobile computing settings. The framework provides people, places, and things with computational functionalities to support and annotate them. Using location-tracking systems, the framework provides a way for mobile agents to follow their users as they move around. A prototype implementation of the framework has been built on a Java-based mobile agent system and tested with several practical applications, including follow-me applications and a user navigational assistance system. The second paper ‘Power-aware broadcasting and activity scheduling in ad hoc wireless networks using connected dominating sets’ by J. Wu and B. Wu and I. Stojmenovic addresses the broadcasting issue in an ad hoc network. A straightforward broadcasting by flooding is usually very costly and will result in substantial redundancy and more energy consumption. A new broadcasting based on connected dominating sets is proposed. The authors propose to apply the notion of power-aware connected dominating set to broadcasting and activity scheduling. The effectiveness of the proposed method in prolonging the life span of the network is confirmed. The third paper ‘Reliable MAC layer multicast in IEEE 802.11 wireless networks’ by M. Sun, L. Huang, S. Wang, A. Arora and T.-H. Lai addresses the multicast/broadcast support in an IEEE 802.11 wireless network. The IEEE 802.11 multicast/broadcast protocol is designed based on CSMA/CA and does not provide any MAC layer recovery on multicast/broadcast frames, thus suffering from the reliability problem. To redress the problems of reliability and efficiency, the authors propose a reliable Batch Mode Multicast MAC protocol, which considerably reduces the time required for a multicast/broadcast. Then the authors further propose a Location Aware Multicast MAC protocol that uses station location information to further improve the performance. One of the most important applications for mobile commerce is location-based application and location determination technology. In the fourth paper entitled

Sales Supporting System using Mobile Agent Technology

We have developed a system for sales staff to access database systems which contain the information on customers and travel plans through mobile terminals, such as a notebook Personal Computer (PC), from their location. This system uses a Java-based mobile agent system. Although it takes a comparatively long time for the first retrieval because the agent has to move to the mobile terminal, it is allowable for practical use. After the first retrieval, the communication time is nearly equal to the time for data transmission. We also propose the Intranet configuration where the mobile terminal can access to the server from on-board Local Area Network (LAN).

Comparing the performance of mobile agent systems: a study of benchmarking

In the past few years there has been an enthusiastic interest in mobile agent technology and several platforms have been developed. Some of them have only been used for research purposes while others have been deployed as commercial products. The community is now looking for applications where these platforms can be effectively used. Some comparisons about the functionality of some mobile agent systems have been presented in the literature. However, to the best of our knowledge, there has been no reported study that compares the real performance of the platforms. In this paper, we present the first results of an experimental study that compares the performance of eight Java-based Mobile Agent systems: Aglets, Concordia, Voyager, Odyssey, Jumping Beans, Grasshopper, Swarm and James. This study presents some insights about the performance and the robustness of each platform.