Using a generalized instance set for automatic text categorization
Proceedings of the 21st annual international ACM SIGIR conference on Research and development in information retrieval
Globally Distributed Content Delivery
IEEE Internet Computing
Adaptive filters for continuous queries over distributed data streams
Proceedings of the 2003 ACM SIGMOD international conference on Management of data
ACM Transactions on Database Systems (TODS)
Edgecomputing: extending enterprise applications to the edge of the internet
Proceedings of the 13th international World Wide Web conference on Alternate track papers & posters
Construction of a Coherency Preserving Dynamic Data Dissemination Network
RTSS '04 Proceedings of the 25th IEEE International Real-Time Systems Symposium
Executing incoherency bounded continuous queries at web data aggregators
WWW '05 Proceedings of the 14th international conference on World Wide Web
Sketching streams through the net: distributed approximate query tracking
VLDB '05 Proceedings of the 31st international conference on Very large data bases
Client assignment in content dissemination networks for dynamic data
VLDB '05 Proceedings of the 31st international conference on Very large data bases
Approximate Data Collection in Sensor Networks using Probabilistic Models
ICDE '06 Proceedings of the 22nd International Conference on Data Engineering
Maintaining coherency of dynamic data in cooperating repositories
VLDB '02 Proceedings of the 28th international conference on Very Large Data Bases
Stochastic consistency, and scalable pull-based caching for erratic data stream sources
VLDB '04 Proceedings of the Thirtieth international conference on Very large data bases - Volume 30
Model-driven data acquisition in sensor networks
VLDB '04 Proceedings of the Thirtieth international conference on Very large data bases - Volume 30
A survey on dynamic Web content generation and delivery techniques
Journal of Network and Computer Applications
Priority based selection to improve contents consistency for mobile overlay network
WCNC'09 Proceedings of the 2009 IEEE conference on Wireless Communications & Networking Conference
Network imprecision: a new consistency metric for scalable monitoring
OSDI'08 Proceedings of the 8th USENIX conference on Operating systems design and implementation
Maintaining coherent views over dynamic distributed data
ICDCIT'10 Proceedings of the 6th international conference on Distributed Computing and Internet Technology
Data-based research at IIT Bombay
ACM SIGMOD Record
Ratio threshold queries over distributed data sources
Proceedings of the VLDB Endowment
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Continuous queries are used to monitor changes to time varying data and to provide results useful for online decision making. Typically a user desires to obtain the value of some aggregation function over distributed data items, for example, to know (a) the average of temperatures sensed by a set of sensors (b) the value of index of mid-cap stocks. In these queries a client specifies a coherency requirement as part of the query. In this paper we present a low-cost, scalable technique to answer continuous aggregation queries using a content distribution network of dynamic data items. In such a network of data aggregators, each data aggregator serves a set of data items at specific coherencies. Just as various fragments of a dynamic web-page are served by one or more nodes of a content distribution network, our technique involves decomposing a client query into sub-queries and executing sub-queries on judiciously chosen data aggregators with their individual sub-query incoherency bounds. We provide a technique of getting the optimal query plan (i.e., set of sub-queries and their chosen data aggregators) which satisfies client query.s coherency requirement with least cost, measured in terms of the number of refresh messages sent from aggregators to the client. For estimating query execution cost, we build a continuous query cost model which can be used to estimate the number of messages required to satisfy the client specified incoherency bound. Performance results using real-world traces show that our cost based query planning leads to queries being executed using less than one third the number of messages required by existing schemes.