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Identifying frequent items in sliding windows over on-line packet streams

Lukasz Golab, David DeHaan, Erik D. Demaine, Alejandro Lopez-Ortiz, J. Ian Munro
2003 Proceedings of the conference on Internet measurement conference - IMC '03  
We present a deterministic algorithm for identifying frequent items in sliding windows defined over real-time packet streams.  ...  While several results exist for computing frequent item queries using limited memory in the infinite stream model, in this paper we consider the limited-memory sliding window model.  ...  If the entire window fits in main memory, answering threshold queries over sliding windows is simple: we maintain frequency counts of each distinct item in the window and update the counters as new items  ... 
doi:10.1145/948224.948227 fatcat:vdx34pf4h5hlhnr3xqoryiw2qi

Identifying frequent items in sliding windows over on-line packet streams

Lukasz Golab, David DeHaan, Erik D. Demaine, Alejandro Lopez-Ortiz, J. Ian Munro
2003 Proceedings of the 2003 ACM SIGCOMM conference on Internet measurement - IMC '03  
We present a deterministic algorithm for identifying frequent items in sliding windows defined over real-time packet streams.  ...  While several results exist for computing frequent item queries using limited memory in the infinite stream model, in this paper we consider the limited-memory sliding window model.  ...  If the entire window fits in main memory, answering threshold queries over sliding windows is simple: we maintain frequency counts of each distinct item in the window and update the counters as new items  ... 
doi:10.1145/948205.948227 dblp:conf/imc/GolabDDLM03 fatcat:lyaejeptnrh2nhauuaip3oibiy

C-SPARQL

Davide Francesco Barbieri, Daniele Braga, Stefano Ceri, Emanuele Della Valle, Michael Grossniklaus
2009 Proceedings of the 18th international conference on World wide web - WWW '09  
C-SPARQL is an extension of SPARQL to support continuous queries over RDF data streams.  ...  Supporting streams in RDF format guarantees interoperability and opens up important applications, in which reasoners can deal with knowledge that evolves over time.  ...  The next query counts how many cars went through each tollgate in the last 10 minutes, sliding the window every minute.  ... 
doi:10.1145/1526709.1526856 dblp:conf/www/BarbieriBCVG09 fatcat:isars3o6dvay3cgq2n7sp4au34

Querying Sliding Windows Over Online Data Streams [chapter]

Lukasz Golab
2004 Lecture Notes in Computer Science  
Processing continuous queries over data streams introduces a number of research problems, one of which concerns evaluating queries over sliding windows defined on the inputs.  ...  In this paper, we describe our research on sliding window query processing, with an emphasis on query models and algebras, physical and logical optimization, efficient processing of multiple windowed queries  ...  For example, the Cartesian product is straightforward to evaluate over sliding windows, but intractable over infinite streams.  ... 
doi:10.1007/978-3-540-30192-9_1 fatcat:wsecmjqfxbcfjl5pm4lpiyeyo4

Sliding HyperLogLog: Estimating Cardinality in a Data Stream over a Sliding Window

Yousra Chabchoub, Georges Hebrail
2010 2010 IEEE International Conference on Data Mining Workshops  
It has the advantage to estimate at any time the number of flows seen over any duration bounded by the length of the sliding window.  ...  This algorithm adapts the HyperLogLog algorithm of Flajolet et al to the data stream processing by adding a sliding window mechanism.  ...  For both cases, the objective is to count the number of flows over a sliding time window.  ... 
doi:10.1109/icdmw.2010.18 dblp:conf/icdm/ChabchoubH10 fatcat:kmslxz5ibreyhooywnujk2pz74

How can sliding HyperLogLog and EWMA detect port scan attacks in IP traffic?

Yousra Chabchoub, Raja Chiky, Betul Dogan
2014 EURASIP Journal on Information Security  
It is composed of two complementary parts: First, a probabilistic counting part, where the number of distinct destination ports is estimated by adapting a method called 'sliding HyperLogLog' to the context  ...  less than 22 kb and has a very good accuracy on the estimation of the number of destination ports (a relative error of about 3.25%), which is in agreement with the theoretical bounds provided by the sliding  ...  In this context, the sliding HyperLogLog algorithm can be applied to count indefinitely, over a sliding window, the number of distinct destination ports.  ... 
doi:10.1186/1687-417x-2014-5 fatcat:rvyjy7zwpfhu5p2nmad2hbr7ka

Semantics of Spatially-Aware Windows Over Streaming Moving Objects

Kostas Patroumpas, Timos Sellis
2007 2007 International Conference on Mobile Data Management  
Several window constructs are usually specified in continuous queries over data streams as a means of limiting the amount of data processed each time and thus providing real-time responses.  ...  We systematically examine the particular case of spatiotemporal streams generated from moving point objects and we introduce a comprehensive classification of window variants useful in expressing the most  ...  Window variants are often classified according to their evolution with time (sliding, tumbling, landmark windows) or through a presumptive succession in arriving items (count-based or partitioned) [12  ... 
doi:10.1109/mdm.2007.17 dblp:conf/mdm/PatroumpasS07 fatcat:ub74aatkezcvxlka5iageleqmm

Multi-scale Windowing over Trajectory Streams [chapter]

Kostas Patroumpas
2012 Lecture Notes in Computer Science  
over trajectory streams -Focus on motion over varying time horizons in the past • Sliding windows at subsumable time horizons[TIME'10] -Effectively, each window frame represents a granularity level  ...  window bounds Time-based Filtering SeCoGIS'12 • A demultiplexing phase per frame -Partition items in into distinct paths • : time-ordered positions per object -Still, filtered data may be  ... 
doi:10.1007/978-3-642-33999-8_35 fatcat:4sncwdwk4bhmbofvwz4mebf3ka

Evaluating top-k queries over incomplete data streams

Parisa Haghani, Sebastian Michel, Karl Aberer
2009 Proceeding of the 18th ACM conference on Information and knowledge management - CIKM '09  
We show that even with object pruning the necessary storage for exact evaluation of top-k queries is linear in the size of the sliding window.  ...  Assuming a sliding window model, this general problem has been a well addressed research topic in recent years.  ...  FM sketches [16] which are among hashing sketches are used for distinct item counting over streams.  ... 
doi:10.1145/1645953.1646064 dblp:conf/cikm/HaghaniMA09 fatcat:nv2hxoajifacbcvv63rdqbsl6e

Mining frequent itemsets over tuple-evolving data streams

Chongsheng Zhang, Yuan Hao, Mirjana Mazuran, Carlo Zaniolo, Hamid Mousavi, Florent Masseglia
2013 Proceedings of the 28th Annual ACM Symposium on Applied Computing - SAC '13  
We present a theoretical analysis for mining frequent itemsets from sliding windows over such data.  ...  Moreover, we provide a novel verification method that efficiently computes the counts of candidate itemsets.  ...  The first sliding window in the figure contains all distinct users. We can extract AC and BE, which are frequent in this window.  ... 
doi:10.1145/2480362.2480419 dblp:conf/sac/ZhangHMZMM13 fatcat:vrnebwooirahhejqn56xwscwmy

Spatiotemporal aggregate computation: a survey

I.F.V. Lopez, R.T. Snodgrass, Bongki Moon
2005 IEEE Transactions on Knowledge and Data Engineering  
Typically, applications modeling spatiotemporal objects need to process vast amounts of data.  ...  s aRB-tree is the distinct counting problem.  ...  [72] recognize the distinct count problem within the aRB-tree and presented an approximate approach to evaluating distinct COUNT and distinct SUM aggregate queries.  ... 
doi:10.1109/tkde.2005.34 fatcat:j54z4j2chzgchnyqdwoilwnpjy

Neighbor-based pattern detection for windows over streaming data

Di Yang, Elke A. Rundensteiner, Matthew O. Ward
2009 Proceedings of the 12th International Conference on Extending Database Technology Advances in Database Technology - EDBT '09  
However, pattern detection with sliding window semantics, as required by applications ranging from stock market analysis to moving object tracking , remains largely unexplored.  ...  To overcome this, we exploit the "predictability" property of sliding windows to elegantly discount the effect of expiring objects on the remaining pattern structures.  ...  Sliding window semantics assume a window size (either a time interval or a count of objects), with the pattern detection results generated based on the most recent data that fall into the sliding window  ... 
doi:10.1145/1516360.1516422 dblp:conf/edbt/YangRW09 fatcat:4bdrh36vgvdm5bnbutkrqywku4

Maintaining consistent results of continuous queries under diverse window specifications

Kostas Patroumpas, Timos Sellis
2011 Information Systems  
Although sliding windows get frequently employed in many user requests, additional types like partitioned or landmark windows are also available in stream processing engines.  ...  Continuous queries applied over nonterminating data streams usually specify windows in order to obtain an evolving -yet restricted-set of tuples and thus provide timely and incremental results.  ...  This important work is perhaps the closest in spirit with our own, but their objective is entirely concentrated on time-based sliding windows.  ... 
doi:10.1016/j.is.2010.02.001 fatcat:d25ayczu7zdhbokhf2ogehrfne

Window Specification over Data Streams [chapter]

Kostas Patroumpas, Timos Sellis
2006 Lecture Notes in Computer Science  
In this paper, we describe a formal framework for expressing windows in continuous queries over data streams.  ...  After classifying windows according to their basic characteristics, we give algebraic expressions for the most significant window types commonly appearing in applications.  ...  As for count-based sliding windows, each incoming tuple throws away the oldest one.  ... 
doi:10.1007/11896548_35 fatcat:hiqzb2un4veixohif2lsk75oha

Multi-granular Time-Based Sliding Windows over Data Streams

Kostas Patroumpas, Timos Sellis
2010 2010 17th International Symposium on Temporal Representation and Reasoning  
We introduce a multi-level window operator that concurrently spans temporal extents of increasing granularity over a streaming dataset.  ...  This windowing construct is inherently sliding with time, essentially providing at each granularity a varying, but always finite portion of the most recent stream items.  ...  However, space cost escalates linearly with distinct count r of recurring items (plotted for r = 5, 10), since a separate bitmap is required per distinct item.  ... 
doi:10.1109/time.2010.14 dblp:conf/time/PatroumpasS10 fatcat:w4eyp4aw25gcxkhkojh72zxn4i
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