Cache Coherency in Location-Dependent Information Services for Mobile Environment

  • Jianliang Xu
  • Xueyan Tang
  • Dik Lun Lee
  • Qinglong Hu
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1748)


Caching frequently accessed data at the client is an attractive technique for improving access time. In a mobile computing environment, client location becomes a piece of changing information. As such, location-dependent data may become obsolete due to data updates or client movements. Most of the previous work investigated cache invalidation issues related to data updates only, whereas few considered data inconsistency caused by client movements. This paper separates location-dependent data invalidation from traditional cache invalidation. For location-dependent invalidation, several approaches are proposed and their performance is studied by a set of simulation experiments. The results show that the proposed methods substantially outperform the NSI scheme which drops the cache contents entirely when hand-off.


Data Item Service Area Mobile Client Query Answer Cache Coherency 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1999

Authors and Affiliations

  • Jianliang Xu
    • 1
  • Xueyan Tang
    • 1
  • Dik Lun Lee
    • 1
  • Qinglong Hu
    • 1
  1. 1.University of Science and TechnologyClear Water BayHong Kong

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