In mobile wireless communication network, caching data items at the mobileclients is important to reduce the data access delay. However, efficient cacheinvalidation strategies are used to ensure the consistency between the data inthe cache of mobile clients and at the database server. Servers useinvalidation reports (IRs) to inform the mobile clients about data itemupdates. This paper proposes and implements a multicast based strategy tomaintain cache consistency in mobile environment using AVI as the cacheinvalidation scheme. The proposed algorithm is outlined as follows - To resolvea query, the mobile client searches its cache to check if its data is valid. Ifyes, then query is answered, otherwise the client queries the DTA (DynamicTransmitting Agent) for latest updates and the query is answered. If DTAdoesn't have the latest updates, it gets it from the server. So, the main ideahere is that DTA will be multicasting updates to the clients and hence theclients need not uplink to the server individually, thus preserving the networkbandwidth. The scenario of simulation is developed in Java. The resultsdemonstrate that the traffic generated in the proposed multicast model issimplified and it also retains cache consistency when compared to the existingmethods that used broadcast strategy.
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