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The performance of physical assets has become a major determinant success factor for urban flood control. However, managing these assets is always challenging as there are a huge number of diverse assets involved, which are distributed throughout the city, and owned by different agencies. Aiming at improving the management efficiency of these assets, and ensuring their performance, this paper proposes the concept of cloud asset based on cloud computing, mobile agent, and various smart devices. Through hardware integration and software encapsulation, cloud asset could sense its real-time status, adapt to varied working scenarios, be controlled remotely, and shared among agencies. It enables accurate real-time control of every asset, and thus improves the management efficiency and effectiveness. This paper first presents the concept of cloud asset with its technical architecture, and then analyses the software agent model for cloud asset, which is the key enabler to realize UPnP (Universal Plug and Play) management of assets, and provides mobility and intelligence for them. After that, the framework of cloud asset-enabled workflow management is built, in which cloud asset could be easily found and dynamically invoked by different workflows. Finally, a demonstrative case is provided to verify the effectiveness of cloud asset. [ABSTRACT FROM AUTHOR]

A wireless sensor network (WSN) consists of spatially distributed nodes that monitor physical conditions. Thus far, WSNs have been constructed for specific applications. However, in the future, system operators may want an existing WSN to deploy simultaneous applications. Existing studies have demonstrated the effectiveness of applying mobile agents to enable simultaneous applications in WSNs. However, two problems make the present form of mobile agents impractical for applications involving cooperation and group migration by mobile agents. The first problem is the lack of a suitable architecture enabling cooperation and interaction between agents, and the second is the lack of an efficient way of achieving group migration by agents in WSNs. To address these problems, we propose an architecture organized by mobile agents that has specific functionalities and that enables group migration by multiple agents. [ABSTRACT FROM AUTHOR]

Abstract: Mobile agent-based distributed job workflow execution requires the use of execution coordination techniques to ensure that an agent executing a subjob can locate its predecessors’ execution results. This paper describes the classification, implementation, and evaluation of execution coordination techniques in the mobile agent-based distributed job workflow execution system. First, a classification of the existing execution coordination techniques is developed for mobile agent systems. Second, to put the discussion into perspective, our framework for mobile agent-based distributed job workflow execution over the Grid (that is, MCCF: Mobile Code Collaboration Framework) is described. How the existing coordination techniques can be applied in the MCCF is also discussed. Finally, a performance study has been conducted to evaluate three coordination techniques using real and simulated job workflows. The results are presented and discussed in the paper. [Copyright &y& Elsevier]

As a recently emerging distributed computing paradigm, mobile-agent technology attracts great interests because of its salient merits. However, it also brings significant security concerns, among which the security problems between a mobile agent and its platforms are of primary importance. While protecting a platform (platform or host security) can benefit from the security measures in a traditional client-server system, protecting a mobile agent (mobile-agent or code security) has not been met in traditional client-server systems and is a new area emerging with mobile-agent technology. Mobile-agent security is also believed to be the most difficult in the security areas of a mobile-agent system. Several methods are proposed to provide protection or detection mechanisms for mobile-agent security. However, many of them either lack an intuitive formal approach to formally model and analyze the system or lack security consideration for mobility-the most distinct characteristic of a mobile agent. In this paper, we extended the original elementary object system (EOS), which applies object-oriented technology to Petri nets, in several aspects because the original EOS cannot fully support the features of mobile-agent system and security modeling. Based on the extended EOS (EEOS), we developed a formal model for a generic secure mobile-agent system. This model supports not only strong mobility but also secure mobility of a mobile agent. Mutual authentication between a mobile agent and its hosting platform is accomplished in this model. Meanwhile, a security mechanism is presented for the detection of malicious platform attacks to mobile-agent code or execution flow during the mobile- agent execution. Using an intuitively graphical formal method to model, simulate, and analyze a secure mobile-agent system distinguishes this paper from other works on mobile-agent security. This paper also introduces how to translate our EEOS model to a colored Petri net (CPN) model and presents the simulation of a sample mobile-agent system model in Design/CPN Different from the mathematical or theorem-proving analysis methods used by other mobile-agent system and mobility models, we used simulation-based analysis to verify several characteristics including boundedness, liveness, concurrence, and security of the system. Compared with other analysis methods, simulation-based analysis is generally more intuitive and more widely used in industry to solve real problems. [ABSTRACT FROM AUTHOR]

A mobile agent is an important platform for applications for the coming ubiquitous society. Many different kinds of mobile agent platforms have been developed. However, agents from one agent platform are generally not able to migrate into another agent platform. As a solution to this problem, we propose an interoperability concept using an incarnation agent. The concept realizes logical mobility within different kinds of agent platforms. The incarnation agent extracts an agent's procedures and status, compiling them into agent platform independent format and then re-compiling them to target agent platform format, thus enabling the process to continue. The incarnation agent also has autonomy for interoperability. It manages complex migration for interoperability, so agent's procedure can be described in simple mobile model. Moreover, the incarnation agent modifies agent's procedures as applicable to facilities of target agent platform. This paper also reports an interoperability middle-ware and its examination. The middle-ware is a foundation of realizing the Incarnation Agent, and the response time and network traffic overheads by the interoperability middle-ware has been measured. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 161(4): 49–59, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20388 [ABSTRACT FROM AUTHOR]

A black hole is a highly harmful stationary process residing in a node of a network and destroying all mobile agents visiting the node without leaving any trace. The Black Hole Search is the task of locating all black holes in a network by exploring it with mobile agents. We consider the problem of designing the fastest Black Hole Search, given the map of the network and the starting node. We study the version of this problem that assumes that there is at most one black hole in the network and there are two agents, which move in synchronized steps. We prove that this problem is NP-hard in arbitrary graphs (even in planar graphs), solving an open problem stated in [J. Czyzowicz, D. Kowalski, E. Markou, A. Pelc, Searching for a black hole in tree networks, in: Proc. 8th Int. Conf. on Principles of Distributed Systems, OPODIS 2004, 2004, pp. 34–35. Also: Springer LNCS, vol. 3544, pp. 67–80]. We also give a -approximation algorithm, showing the first non-trivial approximation ratio upper bound for this problem. Our algorithm follows a natural approach of exploring networks via spanning trees. We prove that this approach cannot lead to an approximation ratio bound better than 3/2. [Copyright &y& Elsevier]

A black hole is a highly harmful stationary process residing in a node of a network and destroying all mobile agents visiting the node, without leaving any trace. We consider the task of locating a black hole in a (partially) synchronous network, assuming an upper bound on the time of any edge traversal by an agent. The minimum number of agents capable to identify a black hole is two. For a given graph and given starting node we are interested in the fastest possible black hole search by two agents, under the general scenario in which some subset of nodes is safe and the black hole can be located in one of the remaining nodes. We show that the problem of finding the fastest possible black hole search scheme by two agents is NP-hard, and we give a 9.3-approximation for it. [ABSTRACT FROM AUTHOR]

This paper presents a framework for reusable mobile agents for network management in the sense that they are independent of either particular networks or applications. The framework enables a mobile agent to be composed from two layered components, which are mobile agents. The former is a carrier of the latter over particular networks independent of any management tasks and the latter defines management tasks performed at each host independently of any networks. The framework also oilers a mechanism for matchmaking the two components. Since the mechanism is formulated on a process algebra approach, it can accurately select the appropriate itinerary component to perform management tasks at hosts that the tasks want to visit over networks. The framework provides a methodology for easily developing and operating mobile agents for traveling among multiple sub-networks to perform their management tasks at all of the nodes that they visit. This paper also describes the framework, its prototype implementation, and a practical application. [ABSTRACT FROM AUTHOR]

This paper discusses methods of sending messages from a source that created a mobile agent (MA) to the MA, which has moved. These methods include the Home-Proxy method and Broadcast method. However, with these techniques, it is possible that the transmitted messages may not be delivered to an MA that is frequently moving around on the network. A method for resolving this problem has been proposed by Murphy and Picco (hereafter termed the Murphy method). Although the Murphy method can reliably deliver messages to the MA, it does not take into consideration the time that elapses until the messages are delivered to the MA. The authors propose a method for delivering messages in the shortest possible time (hereafter termed the clustering method) by partitioning the entire network into multiple areas (clusters) to improve this Murphy method. This paper, proposes the clustering method precisely and in detail. In addition, the validity of this method is certified by performing a logical verification. Simulation experiments are performed to compare the method and Murphy method to prove the effectiveness of the method by verifying that the time required to deliver messages to the MA decreases if the time that an MA stays at a node is not short and that the number of messages decreases if the time that an MA stays at a node is short. © 2005 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 89(1): 67–80, 2006; Published online in Wiley InterScience (www.interscience.wiley. com). DOI 10.1002/ecja.20184 [ABSTRACT FROM AUTHOR]

This paper investigates a human walking behavior- based mobile robot control system. The Intelligent Space (iSpace) is a distributed sensory system, which is the background infrastructure to observe human walking in a limited area. The observation of human walking behavior is applied to train fuzzy-neural networks (FNN). The trained FNNs are applied to approximate the obstacle avoidance behavior of human walking. The paper introduces the iSpace and the mobile agents, which are mobile robots, utilizing the intelligence of the iSpace. The observed and trained human walking behaviors are applied to control the mobile agent in a human-robot shared environment. Experimental results demonstrate the effectiveness of the FNN-based control system. [ABSTRACT FROM AUTHOR]

Mobile agent technology has been applied to develop the solutions for various kinds of parallel and distributed computing problems. However, performance evaluation of mobile agent algorithms remains a difficult task, mainly due to the characteristics of mobile agents such as distributed and asynchronous execution, autonomy and mobility. This paper proposes a general approach based on direct execution simulation for evaluating the performance of mobile agent algorithms by collecting and analyzing the information about the agents during their execution. We describe the proposed generic simulation model, named MADES, the architecture of a software environment based on MADES, and a prototype implementation. A mobile agent-based distributed load balancing algorithm has been used for experiments with the prototype. [ABSTRACT FROM AUTHOR]

We constructed an information retrieval system using mobile agent technology and evaluated it for safety inquiry at disasters. The reason we used mobile agents is robustness against disasters and decrease of communication load. Failure, shutdown, and recovery of communication lines may occur in a large scale and high frequency at disasters, but the agent software autonomously detours or waits and brings back retrieval results. Retrieval is done from outside to inside of the stricken area. We conducted experiments using the agent method, Client/Server (C/S) method, and a combination of the two, and evaluated the results based on traffic amount and response time. We verified that information retrieval by mobile agents has robustness against disasters, and becomes more effective in order to decrease traffic on terminal lines compared with C/S method, as the number of retrievals and the number of migrated servers get larger. © 2002 Scripta Technica, Electron Comm Jpn Pt 1, 85(6): 53–63, 2002 [ABSTRACT FROM AUTHOR]

In recent years, attention was drawn to mobile agents that perform assigned tasks while moving around the network. Mobile agents can efficiently use network resources by moving around the network in a dynamic manner. In this paper, we propose a novel arrangement for interagent communications required for the cooperation between multiple mobile agents performing the same task. In order to support communication between multiple mobile agents, a so-called tracking agent is used that implements a seamless interagent communication so that the agents do not have to know their mutual positions and movement details. It is expected that due to mobility of the tracking agent, it will be possible to reduce delays in message transmission in the case of localized mobile agents. © 2001 Scripta Technica, Electron Comm Jpn Pt 1, 84(5): 11–20, 2001 [ABSTRACT FROM AUTHOR]