An Effective Multicast Strategy for Wireless and Mobile Networks

In Wireless and Mobile Networks, caching data items at mobile clients reduces data access delay. An efficient cache invalidation strategy is used to ensure consistency between the data in cache of mobile clients and database server. The servers in conventional cache consistency schemes used periodic broadcast of Invalidation Reports to report updates of data to the mobile clients or the mobile clients could uplink to the server to know the current update of the data of their interest. Wireless Broadcast allows a huge population of clients to receive information without actively participating in communication. Although scalable, it creates lot of traffic on the network and is not sufficiently secure. In proposed method to resolve a query the mobile client searches its cache to check if its data is valid. If yes, then the query is answered by using cached data, otherwise the client queries the Data Transmitting Agent (DTA) for latest updates and the query is answered. If DTA doesn¿t have the latest updates, it gets it from the server. The DTA multicasts updates to clients having similar interests and they need not uplink to the server individually, thus preserving network bandwidth