Review of Some Transaction Models used in Mobile Databases

Mobile computing is presently experiencing a period of unprecedented growth with the convergence of communication and computing capabilities of mobile phones and personal digital assistant. However, mobile computing presents many inherent problems that lead to poor network connectivity. To overcome poor connectivity and reduce cost, mobile clients are forced to operate in disconnected and partially connected modes. One of the main goals of mobile data access is to reach the ubiquity inherent to the mobile systems: to access information regardless of time and place. Due to mobile systems restrictions such as, for instance, limited memory and narrow bandwidth, it is only natural that researchers expend efforts to soothe such issues. This work approaches the issues regarding the cache management in mobile databases, with emphasis in techniques to reduce cache faults while the mobile device is either connected, or with a narrow bandwidth, or disconnected at all. Thus, it is expected improve data availability while a disconnection. Here in the paper, we try to describe various mobile transaction models, focusing on versatile data sharing mechanisms in volatile mobile environments

Review of Some Transaction Models used in Mobile Databases

Mobile computing is presently experiencing a period of unprecedented growth with the convergence of communication and computing capabilities of mobile phones and personal digital assistant. However, mobile computing presents many inherent problems that lead to poor network connectivity. To overcome poor connectivity and reduce cost, mobile clients are forced to operate in disconnected and partially connected modes. One of the main goals of mobile data access is to reach the ubiquity inherent to the mobile systems: to access information regardless of time and place. Due to mobile systems restrictions such as, for instance, limited memory and narrow bandwidth, it is only natural that researchers expend efforts to soothe such issues. This work approaches the issues regarding the cache management in mobile databases, with emphasis in techniques to reduce cache faults while the mobile device is either connected, or with a narrow bandwidth, or disconnected at all. Thus, it is expected improve data availability while a disconnection. Here in the paper, we try to describe various mobile transaction models, focusing on versatile data sharing mechanisms in volatile mobile environments

Performance Analysis of Distributed Cache Invalidation Method in Mobile Ad hoc Networks using AODV and AOMDV Routing Protocols

Mobile Ad hoc Networks (MANETs) is an active wireless network that can be formed without any existing permanent framework networks. Mobile Ad hoc Networks is an independent structure of mobile nodes communicated with wireless channels. Distributed cache invalidation method is performed among intermediate routing mobile nodes. In MANETs routing protocols are provided desirable route establishments of the mobile nodes. Ad hoc On-demand distance vector routing protocol (AODV) was well known single route protocol , Ad hoc On-demand Multipath Distance Vector routing protocol (AOMDV) is extends the AODV protocol with multipath. These results are carried out in network simulator version2 (NS2), the performance is analyzed and compared between AODV and AOMDV routing protocols

Leveraging the Cloud for Software Security Services.

This thesis seeks to leverage the advances in cloud computing in order to address modern security threats, allowing for completely novel architectures that provide dramatic improvements and asymmetric gains beyond what is possible using current approaches. Indeed, many of the critical security problems facing the Internet and its users are inadequately addressed by current security technologies. Current security measures often are deployed in an exclusively network-based or host-based model, limiting their efficacy against modern threats. However, recent advancements in the past decade in cloud computing and high-speed networking have ushered in a new era of software services. Software services that were previously deployed on-premise in organizations and enterprises are now being outsourced to the cloud, leading to fundamentally new models in how software services are sold, consumed, and managed. This thesis focuses on how novel software security services can be deployed that leverage the cloud to scale elegantly in their capabilities, performance, and management. First, we introduce a novel architecture for malware detection in the cloud. Next, we propose a cloud service to protect modern mobile devices, an ever-increasing target for malicious attackers. Then, we discuss and demonstrate the ability for attackers to leverage the same benefits of cloud-centric services for malicious purposes. Next, we present new techniques for the large-scale analysis and classification of malicious software. Lastly, to demonstrate the benefits of cloud-centric architectures outside the realm of malicious software, we present a threshold signature scheme that leverages the cloud for robustness and resiliency.Ph.D.Computer Science & EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/91385/1/jonojono_1.pd

Knowledge Discovery in the SCADA Databases Used for the Municipal Power Supply System

This scientific paper delves into the problems related to the develop-ment of intellectual data analysis system that could support decision making to manage municipal power supply services. The management problems of mu-nicipal power supply system have been specified taking into consideration modern tendencies shown by new technologies that allow for an increase in the energy efficiency. The analysis findings of the system problems related to the integrated computer-aided control of the power supply for the city have been given. The consideration was given to the hierarchy-level management decom-position model. The objective task targeted at an increase in the energy effi-ciency to minimize expenditures and energy losses during the generation and transportation of energy carriers to the Consumer, the optimization of power consumption at the prescribed level of the reliability of pipelines and networks and the satisfaction of Consumers has been defined. To optimize the support of the decision making a new approach to the monitoring of engineering systems and technological processes related to the energy consumption and transporta-tion using the technologies of geospatial analysis and Knowledge Discovery in databases (KDD) has been proposed. The data acquisition for analytical prob-lems is realized in the wireless heterogeneous medium, which includes soft-touch VPN segments of ZigBee technology realizing the 6LoWPAN standard over the IEEE 802.15.4 standard and also the segments of the networks of cellu-lar communications. JBoss Application Server is used as a server-based plat-form for the operation of the tools used for the retrieval of data collected from sensor nodes, PLC and energy consumption record devices. The KDD tools are developed using Java Enterprise Edition platform and Spring and ORM Hiber-nate technologies

Cache Invalidation Strategies for Internet-based Vehicular Ad Hoc Networks

Internet-based vehicular ad hoc network (Ivanet) is an emerging technique that combines a wired Internet and a vehicular ad hoc network (Vanet) for developing an ubiquitous communication infrastructure and improving universal information and service accessibility. A key design optimization technique in Ivanets is to cache the frequently accessed data items in a local storage of vehicles. Since vehicles are not critically limited by the storage/memory space and power consumption, selecting proper data items for caching is not very critical. Rather, an important design issue is how to keep the cached copies valid when the original data items are updated. This is essential to provide fast access to valid data for fast moving vehicles. In this paper, we propose a cooperative cache invalidation (CCI) scheme and its enhancement (ECCI) that take advantage of the underlying location management scheme to reduce the number of broadcast operations and the corresponding query delay. We develop an analytical model for CCI and ECCI techniques for fasthand estimate of performance trends and critical design parameters. Then, we modify two prior cache invalidation techniques to work in Ivanets: a poll-each-read (PER) scheme, and an extended asynchronous (EAS) scheme. We compare the performance of four cache invalidation schemes as a function of query interval, cache update interval, and data size through extensive simulation. Our simulation results indicate that the proposed schemes can reduce the query delay up to 69% and increase the cache hit rate up to 57%, and have the lowest communication overhead compared to the prior PER and EAS schemes

Cache Invalidation Strategies for Internet-based Vehicular Ad Hoc Networks

Internet-based vehicular ad hoc network (Ivanet) is an emerging technique that combines a wired Internet and a vehicular ad hoc network (Vanet) for developing an ubiquitous communication infrastructure and improving universal information and service accessibility. A key design optimization technique in Ivanets is to cache the frequently accessed data items in a local storage of vehicles. Since vehicles are not critically limited by the storage/memory space and power consumption, selecting proper data items for caching is not very critical. Rather, an important design issue is how to keep the cached copies valid when the original data items are updated. This is essential to provide fast access to valid data for fast moving vehicles. In this paper, we propose a cooperative cache invalidation (CCI) scheme and its enhancement (ECCI) that take advantage of the underlying location management scheme to reduce the number of broadcast operations and the corresponding query delay. We develop an analytical model for CCI and ECCI techniques for fasthand estimate of performance trends and critical design parameters. Then, we modify two prior cache invalidation techniques to work in Ivanets: a poll-each-read (PER) scheme, and an extended asynchronous (EAS) scheme. We compare the performance of four cache invalidation schemes as a function of query interval, cache update interval, and data size through extensive simulation. Our simulation results indicate that the proposed schemes can reduce the query delay up to 69% and increase the cache hit rate up to 57%, and have the lowest communication overhead compared to the prior PER and EAS schemes