Chandreyee Chowdhury

Estimating Reliability of Mobile Agent System for Mobile Ad Hoc Networks

A mobile agent is a particular type of agent with the ability to migrate from one host to another where it can resume its execution. Mobile agents can be used in applications for wireless network to save bandwidth and time. In this paper we consider dependability aspect, especially reliability issues that need to be addressed before the mobile agents can be used for a broad range of commercial applications in mobile adhoc network (MANET). The MANET introduces new aspects to dependability affecting reliability of the services of the mobile agent based system. In this paper, we propose an algorithm for estimating the task route reliability of mobile agent systems (MAS), which are based on the conditions of the underlying wireless network. The agents can select their route dynamically. The complexity of mobile agent network systems makes it hard to obtain the route reliability of the MAS theoretically; instead we estimate it using Monte Carlo simulation. In this paper, we assume that the MAS consist of a number of independent mobile agents operating simultaneously. The paper estimates the reliability of mobile agent system considering different failures of the underlying network. The results achieved demonstrate the robustness of the proposed algorithm. This paper demonstrates a reliability estimation model for MAS in MANET and shows that reliability is almost independent on the no. of agents (for higher no. of agents) or no. of mobile nodes but highly dependent on the condition of the links especially on the connectivity of the graph.

Reputation based trust management system for MANET

Trust can be interpreted as a subjective belief resulting from past interactions that predicts the future behavior of the trustee. Trust management in distributed and resource-constraint networks, such as mobile ad hoc networks (MANETs) is much more difficult but more crucial than in traditional hierarchical architectures, such as the base station- or access point-centered wireless LANs. Generally, MANET is characterized by decentralized control. Hence no Trusted Third Parties can be used. The trust information or evidence used to evaluate trustworthiness is only provided by peers, i.e. other nodes that form the network. Due to the dynamically changing topology and limited resources (power, bandwidth, computation etc.) the trust evaluation procedure should only rely on local information. In this paper, we propose a reputation-based trust management system for detecting and preventing MANET vulnerabilities. Both active (malicious nodes) and passive (selfish nodes) attacks are investigated and our scheme cooperatively helps the nodes to exclude them from the network while tolerating transient faults. The scheme can work with any on-demand routing protocol. We evaluated the performance of our scheme in a discrete event-simulation environment. The results indicate scalability and robustness of our proposed scheme.

Reliability estimate of mobile agent system for QoS MANET applications

A mobile agent is a particular agent with the ability to migrate from one host to another where it can resume its execution. Mobile agents can be used to save bandwidth and time in wireless and mobile network applications. In this paper we consider reliability issues that need to be addressed before mobile agents can be used for a broad range of commercial applications in mobile adhoc network (MANET). Here we propose an algorithm for estimating the task route reliability of mo bile agent systems (MAS) that is based on the conditions of the underlying wireless network. The agents can select their route dynamically. The complexity of MAS makes it hard to obtain the theoretical route reliability of the MAS; instead we estimate it using Monte Carlo simulation. Smooth Random Mobility Model (SRMM) is used to estimate node location at a particular time. Each mobile agent may have different demands for link capacity depending upon the task it is assigned. So a mobile agent is assumed to move through a path that satisfies its Quality of Service (QoS) requirement in terms of link capacity. Link failures are treated to be transient in nature. In this paper, we assume that the MAS consists of a number of simultaneously operating independent groups of mobile agents. The results that we have achieved demonstrate the robustness of the proposed algorithm.

A consistent checkpointing-recovery protocol for minimal number of nodes in mobile computing system

The vast computing potential of mobile computing systems is often hampered by their susceptibility to transient and independent failures. To add reliability and high availability to such systems, checkpoint based rollback recovery is one of the widely used ones for scientific computing, database, telecommunication and mission critical applications. This paper presents a coordinated nonblocking checkpointing and recovery technique for such systems that handles the constraints posed by the underlying wireless network, efficiently. Here an initiator (an MSS) sends checkpoint requests to all other MSSs and the MSSs send this request only to those MHs, which have communicated in the last checkpointing interval (relieving the wireless network from synchronization overhead). Also all acknowledged messages are logged at the home station of the receiver MH so that only the faulty MHs need to recover in case of failure and no other process is affected by this fault and subsequent recovery.

Power Aware AODV Routing Protocol for MANET

Computation and routing in Mobile Ad hoc Network (MANET) is strongly co-related with power resource. Recent trend is to minimize the power consumption and maximize the computation without hampering the quality of service in MANET. To increase durability, battery resource of a node that has more power than its neighbor nodes could be used for routing and computation. In this paper a power aware routing scheme based on AODV protocol is presented. The protocol focuses on increasing network lifetime by taking into account residual capacity of the nodes with respect to its neighbors, its internal load as well as no. of message transfers. The protocol finds durable routes having nodes with more residual energy. The results achieved demonstrate the robustness of the proposed algorithm.

A reliable service discovery protocol using mobile agents in MANET

Recently mobile agents are being used in many applications for mobile ad hoc networks (MANET) for instance to discover and spread service information among the nodes in MANET. Here agents travel through the network, collecting the dynamically changing service information. However, reliability and availability issues are needed to be addressed while designing mobile agent based (service discovery) protocols before it can be deployed for a broad range of commercial applications in MANET. Since MANET provides a resource constrained dynamic environment, it introduces new aspects to dependability thereby affecting reliability of the services provided by the mobile agent based system. But no work till now addresses the reliability analysis of these protocols or design of such protocols from reliability perspective. In this paper we propose a novel service discovery protocol using mobile agents for MANET with reliable performance for a given MANET configuration. The agents select their route dynamically and exchange service information with the nodes in order to speed up the process. The complexity of such a system makes it hard to obtain the theoretical task route reliability of the provider; instead we estimate it using Monte Carlo simulation. Smooth Random Mobility Model (SRMM) is used to estimate node location at a particular time. Multipath propagation effect of radio signals is also considered. The experimental results show the robustness of the proposed scheme.

Analysis of Energy Efficient Wireless Sensor Networks Routing Schemes

Wireless Sensor Network (WSN) is one of the fastest growing technologies in wireless domain. The sensor nodes are typically lightweight and with limited battery power they are failure-prone too. So, efficient power saving schemes must be designed and developed to optimize energy consumption and thereby improve overall network lifetime. Clustering technique is one of the time-tested approaches that effectively reduce energy consumption. The lifetime of WSNs is enhanced by uniform clustering that balances network load among the clusters. In this paper, we have reviewed various energy efficient clustering schemes applicable in wireless sensor networks. The schemes are analyzed thoroughly and some of them are simulated to assess performance.

Application of mobile agent in VANET for measuring environmental data

In Vehicular Ad hoc NETwork (VANET) vehicles equipped with wireless communication devices communicate with each other to share information or achieve some collaborative goal. Mobile agents because of their adaptability and mobility can be well utilized in designing VANET applications. In this paper, the vehicles in VANET are shown to collect environmental data. Here vehicles equipped with sensors to measure environmental data are sent from a monitoring center to some particular monitoring area. Each vehicle has mobile agent platform that may host one mobile agent. The mobile agent spawned at the monitoring center migrates from one vehicle to the other to reach the monitoring area. It (the agent) collects necessary data, processes it and brings back the result. This helps to measure environmental parameters in different areas without deploying fixed infrastructure and mobile agents ensure better utilization of network bandwidth. The application is simulated in OMNET++ with SUMO to generate road traffic. The results indicate scalability of the application for larger networks. With more no. of vehicles, more area can be covered.

Mobile Agent Security Based on Trust Model in MANET

There is an emerging trend of using mobile agents for wireless network applications. For instance mobile agents can be used to protect the mobile ad hoc network (MANET) itself by using agent based IDS or IPS.In this paper we consider security issues that need to be addressed before multi-agent systems in general, and mobile agents in particular, can be used for a broad range of commercial applications for MANET. Here we propose a distributed scheme to protect both the agents and the host platforms (running at the nodes) from possible threats. This paper seeks to form a distributed trust model of the network. Here the agents and the host platforms work together to so that each trusted node may form a consistent trust view of the network. Each agent is given with a list of nodes (host platforms) to visit by their owner (a node). The agents, while migrating share their view of the trusted hosts to the platform they currently reside. The agents use combination of encryption and digital signature (to create hash code) to provide privacy and authentication services.Here smooth random mobility model is used to generate node mobility. The connectivity between the nodes is decided by the Two-Ray model of radio propagation in order to consider multipath propagation effect. The effect of environmental noise is also studied. Our proposed algorithm is simulated using java and the results show the robustness of our proposed scheme.

AirSense: Opportunistic crowd-sensing based air quality monitoring system for smart city

Citizens are exposed to air pollutants both indoors and outdoors due to their activities, which may result in a variety of health effects. In this paper, we present AirSense, an opportunistic crowd-sensing based air quality monitoring system, aimed at collecting and aggregating sensor data to monitor air pollution in the vicinity and the city. We introduce a light weight, low power and low cost air quality monitoring device (AQMD) and demonstrate how AQMD and smart phone devices in a crowd collaboratively (through offloading) gather and share data of interest to the cloud. In cloud, collected data will be analyzed and an aggregated view will be generated for providing an air pollution heat map of the city. End user can view both the neighborhood (local) air quality and AQImap (air quality index map) of the city on his/her smartphone.