Distributed Network Management with Secured Mobile Agent Support

Mobile agent systems provide new perspectives for distributed e-commerce applications. These applications may present specific restrictions, making mobile agent systems a feasible solution. Even so, mobile agents present some security related problems. An important one is resource access control. The ability for mobile agents to provide a simple, scalable, flexible, and secure access control system is a key point for the widespread adoption of mobile agents. In this paper we propose a mechanism to safely assign roles to mobile agents and an access control method based on Role-based Access Control (RBAC). The access control method provides a simple, lightweight and distributed model for mobile agent applications. It is proposed as an extension of the MARISM-A (An Architecture for Mobile Agents with Recursive Itineraries and Secure Migration) project, a secure mobile agent platform.

Over the last couple of years we have been working on the development of mobile agents systems and their application to the areas of telecommunications and network management. This work has produced positive results: a competitive mobile agent platform was built, the run-time benefits of mobile agents were proved, and our industrial partners have developed practical applications that are being integrated into commercial products. However, despite the positive results, we feel that mobile agent technology is still not ready to enter the path of mainstream software development. In our perspective, one of the main reasons for this situation arises from the traditional approach to mobile agent technology. This approach, based on the familiar concept of the mobile-agent distributed platform as an extension of the operating system, focuses too much on the mobile agents and associated issues (mobility, agent lifecycle, security, coordination, etc.) and provides poor support for the development of applications where mobile agents are just one of several available technologies. Learning from past experience, we are now working on a new approach where the focus is brought back to the applications and mobile agents become just one the tools available to develop distributed systems. This provides a much lighter framework for application-based mobile agent systems. This paper presents the lessons learned from our previous project and discusses the new concept we are developing: application-centric mobile agent systems.

Problem statement: Most of the information retrieval systems used only client-server architectures. The client-server model though powerful, had some limitations. In mobile computing environment which has both wired network and wireless networks with limited communication capabilities, the performance of the system was very low. Approach: Mobile agents are considered a suitable technology to develop applications such as information retrieval system for mobile computing environment. Mobile agents are autonomous and dynamic entities that can migrate between various nodes in the network. They offer many advantages over traditional design methodologies like: reduction in network load, overcoming network latency and disconnected operations. Since the mobile agents do not need continuous communication with the mobile host, they are not affected by the sudden disconnection of wireless network and the situation of turning mobile host off for power saving. In order to get the complete benefit of mobile agent system, the system must be fault tolerant. In the context of mobile agents, fault-tolerance prevents a partial or complete loss of the agent. Results: Our system in mobile computing environment ensured that the agent arrived at its destination with result and performance of the system improved by the way of reduction in the response time. And also, the system allowed sending more requests by the way of creating many mobile agents without affecting the performance. Conclusion: Our research compared the performance of client-server architecture and fault tolerant mobile agent information retrieval system and proved that our system solved the limitations faced by the client server architecture. The system can also be extended to adhoc networks.

Mobile agent technology is used in modern information technology to facilitate interoperability between isolated information systems. In addition, mobile agents have many advantages that make them a viable and attractive option in health sector applications. We propose the development of a health architecture based on integrated mobile agent technology and a service-oriented architecture (SOA) with distributed health applications involving the interoperability of remote or local homogeneous and heterogeneous applications, besides the SOA, and providing support for mobile agents. Furthermore, the SOA can be tested on different platforms. The development of a mobile agent architecture using Health Level Seven, known as HL7, for data exchange in the health sector is an essential step in making it widely accepted by centers that use health records as their means of communication. Each health center’s local data format can be modified for data exchange with other health centers through a mapping process that transforms the data from its local format to HL7, and vice versa. This research introduces a mobile agent architecture that can be applied to distributed health information systems to achieve interoperability.

There are many areas in which mobile agent technology can be deployed. Researchers are now looking at this technology as a solution in their respective research areas, such as information retrieval, distributed computing, and network management. This increase of interest is due the basic characteristics of mobileagents - autonomous and mobile. In the paper, we are exploiting the abovementioned characteristics of mobile agents, and applying this technology in Internetenvironments. Using a mobile agent as a transparent content transcoding proxy in a proxy based network architecture, we show how a mobile proxy agent can be used to improve quality of service provided to the end user connected via heterogeneous access networks, using computing devices which have very different capabilities.

The flexibility offered by mobile agents is quite noticeable in distributed computing environments. However, the greater flexibility of the mobile agent paradigm compared to the client/server computing paradigm comes at an additional threats since agent systems are prone to failures originating from bad communication, security attacks, agent server crashes, system resources unavailability, network congestion, or even deadlock situations. In such events, mobile agents either get lost or damaged (partially or totally) during execution. In this paper, we propose parallel checkpointing approach based on the use of antecedence graphs for providing fault tolerance in mobile agent systems. During normal computation message transmission, the dependency information among mobile agents is recorded in the form of antecedence graphs by participating mobile agents of mobile agent group. When a checkpointing procedure begins, the initiator concurrently informs relevant mobile agents, which minimizes the identifying time. The proposed scheme utilizes the checkpointed information for fault tolerance which is stored in form of antecedence graphs. In case of failures, using checkpointed information, the antecedence graphs and message logs are regenerated for recovery and then normal operation continued. Moreover, compared with the existing schemes, our algorithm involves the minimum number of mobile agents during the identifying and checkpoiting procedure, which leads to the improvement of the system performance. In addition, the proposed algorithm is a domino-free checkpointing algorithm, which is especially desirable for mobile agent systems. Quantitative analysis and experimental simulation show that our algorithm outperforms other coordinated checkpointing schemes in terms of the identifying time and the number of blocked mobile agents and then can provide a better system performance. The main contribution of the proposed checkpointing scheme is the enhancement of graph-based approach in terms of considerable improvement by reducing message overhead, execution, and recovery times.

So far, agent research can be broadly categorized into two areas: intelligent agents and mobile agents. Intelligent agent research has grown from a background of AI, humancomputer interaction, and autonomous systems, while mobile agents research stems from the areas of distributed computing and networked systems. Intelligent agents research addresses intelligent control, planning, domain modeling, user modeling, perception, interagent cooperation, and adaptivity. Intelligent agents can take on many different roles, ranging from representing a human user’s interests to actively collaborating with users and each other. Intelligent agents are being designed to tackle nearly every tedious, non-creative activity that people perform (e.g., Web searches), as well as many more abstract functions (e.g., entertainment). Major issues in intelligent agents research include knowledge representation and communication, architectures for intelligent autonomy, mixed-initiative behavior, collaboration techniques, and learning. Mobile agents address physical communication, agent mobility, tracking and locating mobile agents, security and reliability of agents, etc. Mobile agents are suited for optimizing communication ‐ moving the action towards the source of data ‐ and thereby avoiding the need for huge data transfers. This is beneficial in data-intensive applications such as data mining. Mobility can also improve reliability in certain cases. In the field of electronic commerce, mobile agents naturally reflect the characteristics of buyer and the seller, effectively playing the roles of traveling salesman or broker. They can also be applied for easier software customization, software distribution, and to represent disconnected users. The main issues are in security, providing the infrastructure on the Web (naming, locating, controlling, and messaging) and improving survivability. The biggest challenge for all new agent technology is developing successful applications. For this minitrack, we selected two characteristics of agents that can span the diverging areas of intelligent and mobile agents: mobility and communication. The accepted papers reflect the research issues described in this summary. The minitrack is organized in three sessions. The first session explores the coordination of multiple intelligent agents using dramatically different communication schemes. Andersson and Ygge present an efficient market-based approach to managing very large scale groups of agents engaged in coordination via producer/ consumer transactions. Their CoTree algorithm allows largescale markets to operate efficiently with sparse communication, rapid updates as agent preferences change, and minimal data caching requirements on massively distributed systems. In contrast, Nelson, Penner, and Soken discuss the Interaction Society model of coordination, in which relatively small-scale groups of knowledge-intensive agents collaborate using complex communication about discrete tasking and information requirements. Their model for inter-agent communication and interactions with human users is being applied to build a multi-agent advising system for coordinating military Search and Rescue operations. Finally, Barbuceanu discusses the role of obligations and interdictions in the context of coarse-grain agent interactions. By explicitly capturing social obligations and the costs associated with violating those constraints, he shows how rational agents can achieve coordinated behavior without necessarily sharing goals. The second session addresses Java-based mobile agent systems. The paper by Covaci, Busse and Zhang, describes how a mobile agent system can be used for network management. Their framework is based on existing solutions such as TMN, and can be extended to SNMP.

The security problem of mobile agent is important for applications using mobile agent technology. In this paper, we analyzed the security problems of mobile agent system exposed in opening environment and proposed a method to improve the authentication and credentials management in mobile agent environment. In our design, the trusted computing platform is used as the basic platform to running mobile agent systems, and the trusted platform module will used to help the authentication and credentials management. We also gave a model system for building trusted mobile agent system. In this system, the security of mobile agent is improved by using trusted computing platform which is linked with upper layer applications through the trusted software stack. Then, trusted services for mobile agent, including authentication, credential management and key storage, are supported.

This paper focuses on distributed data mining implemented on mobile agent architecture. The paper describes association rule mining algorithm and the steps to implement on agent architecture. This research focuses on enabling the agents with certain amount of intelligence to apply the domain-specific knowledge to retrieve, filter and classify information, find patterns and make predictions. This paper also focuses on intelligent agent paradigm in the context of information retrieval, filtering, classification and learning using proposed data mining algorithm. The proposed algorithm reduces the database scanning and increases performance.

Mobile agents can provide many benefits to the development of distributed applications. But the mobile agent system will face some security threat since it will run in an opening network environment. In this paper, we analyzed the security threats in mobile agent system and provided a method to build the trusted connect between entities in mobile agent environment. This method uses the trusted platform module in trusted computing platform as the trusted base. When a mobile agent wants to migrate to another platform, it should use a trusted connect between the source host and the goal host. The agent and agent platform can trust with each other. This method will be helpful to build a trusted computing environment for the mobile agent system.

Detecting and resolving deadlocks in mobile agent systems

Nowadays, a lot of e-Learning systems are widely deployed in educational schools. Typical e-Learning systems are implemented as client-server model. In the client-server model, the number of clients affects on the load of the server. In order to reduce the load on the server, we developed a P2P-based distributed e-Learning system. The proposed system consists of a lot of mobile agents which manage study contents and some functions such as scoring, showing questions, and correct answers. When a learner requests content, a mobile agent who has its content comes to the learner's computer, and then he/she can start the study. Here, a mobile agent has to manage multimedia data, which may be a huge size of data. Thus, a mobile agent has to migrates to the learner's node with a huge size of data. Then, the learner cannot start the study until the mobile agent finished to migrate. In order to solve this problem, we divide multimedia data into fragments and prepare mobile agents which manages each fragments. Since each mobile agents become small, a learner can start the study soon without waiting for the migration of a mobile agent which has a huge size of multimedia data. We, however, have to search a mobile agent which manages their fragments. Therefore, a mobile agent which manages n-th fragments informs its location to the agent which manages (n+1)-th fragments, and vice versa. Since each agent knows the location of a mobile agent which manages next and previous fragment, and fragments are cached into learner's node, a learner can play multimedia data smoothly without finding the location of mobile agent which manages holding next fragment. Experiment results show the effectiveness of our method.

Mobile agents are processes that may be dispatched from a source computer and be transported to remote servers for execution. In any mobile agent system, the ability to communicate with agents in real-time is essential for retrieving any data or information that they have collected, and for supporting coordination and cooperation among them. Communication with a mobile agent requires the ability to track it. In the thesis, we propose several distributed mechanisms for tracking (or locating) mobile agents. We first propose a method based on distributed hashing table (DHT) to locate mobile agents efficiently in a large-scale network. The idea is to treat mobile agents and hosts similarly to the way peers are treated in a peer-to-peer system, and to implement a lookup protocol that is based on that principle, while taking care of the mobile nature of the agents. We then introduce a new locating mechanism. Our technique is based on appropriate delays that the mobile agents must perform while moving on the network so to facilitate its tracking, should it be needed. The searching agent computes a particular searching path that will guarantee the tracking within one traversal of the network. We indicate various strategies, and we perform experiments for computing the searching path and for comparing their performances in synchronous and asynchronous settings, in arbitrary and specific topologies.

This paper analyzes mobile agent performance in network management, comparing it with the client-server model used by the SNMP (Simple Network Management Protocol). Response time results show that the mobile agent performs better than the SNMP when the number of managed elements ranges between two limits determined by the number of messages that pass through a backbone and by the mobile agent size that grows with the variables collected on the network elements.KeywordsMobile agentsnetwork managementand scalability

Solutions for system and network management given today are afflicted with two main shortcomings, namely the centralised approach they are based on and the inadequate addressing of heterogeneous environments. While the latter is the main concern of, for example, Web-based management activities, the aspect of centralisation is not being covered to full extend. With regard to the explosive growth of computer systems and networks both in size and complexity, new approaches therefore have to be evaluated which address all problems caused by complexity and heterogeneity. Mobile agent technology is being discussed as a promising new technology for various application areas, with management being one of the most promising. In this paper, problems arising when trying to apply this new technology to system and network management are identified and discussed. The focus is on how to handle the overall complexity with mobile agents, which are limited in size, knowledge, and functionality. An architecture is presented which introduces various types of mobile agents. By determining the required correlation sequence and identifying the co-operation of agents, it is shown how an alarm correlation with mobile agents can be established, which forms the basis for addressing management tasks with mobile agent technology.