Scalable Data Management in Mobile Environments: protocol design in MANETs and data management in mobile sensors

My presentation addressed with two areas of my current research interests: (1) Protocol design in Mobile Ad-hoc Networks, and (2) Sensor data management. It describes briefly the motivating challenges and our approach to dealing with them

Efficient Probabilistic Subsumption Checking for Content-Based Publish/Subscribe Systems

Abstract. Efficient subsumption checking, deciding whether a subscription or publication is covered by a set of previously defined subscriptions, is of paramount importance for publish/subscribe systems. It provides the core system functionality—matching of publications to subscriber needs expressed as subscriptions—and additionally, reduces the overall system load and generated traffic since the covered subscriptions are not propagated in distributed environments. As the subsumption problem was shown previously to be co-NP complete and existing solutions typically apply pairwise comparisons to detect the subsumption relationship, we propose a ‘Monte Carlo type ’ probabilistic algorithm for the general subsumption problem. It determines whether a publication/subscription is covered by a disjunction of subscriptions in O(k md), wherek is the number of subscriptions, m is the number of distinct attributes in subscriptions, and d is the number of tests performed to answer a subsumption question. The probability of error is problem-specific and typically very small, and sets an upper bound on d. Our experimental results show significant gains in term of subscription set reduction which has favorable impact on the overall system performance as it reduces the total computational costs and networking traffic. Furthermore, the expected theoretical bounds underestimate algorithm performance because it performs much better in practice due to introduced optimizations, and is adequate for fast forwarding of subscriptions in case of high subscription rate.

Fast Probabilistic Subsumption Checking for Publish/Subscribe Systems

Efficient subsumption checking, deciding whether a subscription or publication is subsumed (covered) by a set of previously defined subscriptions, is of paramount importance for publish/subscribe systems. It provides the core system functionality, and additionally, reduces the overall system load and generated traffic in distributed environments. As the deterministic solution was shown previously to be co-NP complete and existing solutions typically employ costly pairwise comparisons to detect the subsumption relationship, we propose a probabilistic algorithm for the general subsumption problem. It efficiently determines whether a publication/subscription is covered by a disjunction of subscriptions in $O(k~m~d)$, where $k$ is the number of subscriptions, $m$ is the number of distinct attributes in subscriptions, and $d$ is the number of tests performed to answer a subsumption question. The probability of error is problem specific and typically very small, and determines an upper bound on $d$ in polynomial time prior to the algorithm execution. Our experimental results demonstrate the algorithm performs even better in practice due to introduced optimizations, and is adequate for fast forwarding of publications/subscriptions, especially in resource scarce environments, e.g. sensor networks

06431 Working Group Summary: Atomicity in Mobile Networks

We introduce different mobile network applications and show to which degree the concept of database transactions is required within the applications. We show properties of transaction processing and explain which properties are important for each of the mobile applications. Furthermore, we discuss open questions regarding transaction processing in mobile networks and identify open problems for further research

P2P, ad hoc and sensor networks – All the different or all the same?

Currently, data management technologies are in the process of finding their way into evolving networks, i.e. P2P, ad hoc and wireless sensor networks. We examine the properties, differences and commonalities of the different types of evolving networks, in order to enable the development of adequate technologies suiting their characteristics. We start with presenting definitions for the different network types, before arranging them in a network hierarchy, to gain a clear view of the area. Then, we analyze and compare the example applications for each of the types using different design dimensions. Based on this work, we finally present a comparison of P2P, ad hoc and wireless sensor networks

Information Systems and Economic Intelligence : Proceedings of the 2nd international conference SIIE 2009 : February 12-14, 2009 (in Hammamet, Tunisia)

Information Systems and Economic Intelligence (SIIE'2009) With the advent of globalisation, we sufficiently observe reel cases of agile organisations in diverse socio-economic sectors. These allow us to note the principal competitive elements of organisations founded on economic intelligence practice, knowledge engineering practice as well as use of information and communication technologies. Indeed, the radiance of new frameworks in these organisations emerges from this nascent enterprise culture. They master the analytical and pragmatic precepts of socio-economic environments, technological environments, etc. The founding example by these organisations is to anticipate the phenomenon issuing from globalisation, threats and opportunities for the protection of technical know-how and innovations. It is through the successful experiences of certain that the contours of EI (technological contributions and resources founded on knowledge and technical know-how) appear. This conference reports research works on the following themes: - Information System and Economic Intelligence - Collaborative Information retrieval - Languages and knowledge industries - Economic Intelligence and Management - Cognitive and social dimensions in watch and EI processes - Information Management and knowledge sharing - Intelligent e-Technology - Information systems governanc

Semantic Interoperability in Global Information Systems

Internet, Web and distributed computing infrastructures continue to gain in popularity as a means of communication for organizations, groups and individuals alike. In such an environment, characterized by large distributed, autonomous, diverse, and dynamic information sources, access to relevant and accurate information is becoming increasingly complex. This complexity is exacerbated by the evolving system, semantic and structural heterogeneity of these potentially global, cross-disciplinary, multicultural and rich-media technologies. Clearly, solutions to these challenges require addressing directly a variety of interoperability issues