International Journal of Advanced Networking and Applications

C. Gopala Krishnan ¹, R. Suceendrakumar ²

Affiliations
1 Computer Science and Engineering, IN
2 Department of Computer Science, Sree sastha institute of Engg, Tamil Nadu, IN

Abstract

This work discusses a novel hybrid replacement policy to adopt in the design of our cache. According to our hybrid caching strategy, the results of the most frequently accessed queries are maintained in a static cache of fixed size, which is completely rebuilt at fixed time intervals. Only the queries that cannot be satisfied by the static cache compete for the use of a dynamic cache. Our hybrid cache represents an effective and fast way to address both recency, and frequency of occurrences criteria. While the static cache maintains results of queries that are globally frequent, a simple and fast policy like LRU, which only takes into account query reference recency,could be adopted for the dynamic cache. This novel representation and the associated creation algorithm result in more effective EVRs of window queries. In addition, due to the distinct characteristics, a separate index structures, namely EVR-tree and grid index, for NN queries and window queries, respectively are used. To further increase efficiency, an algorithms to exploit the results of NN queries to aid grid index growth, benefiting EWV creation of window queries is developed. Similarly, the grid index is utilized to support NN query answering and EVR updating. Several experiments for performance evaluation are performed. The experimental results show that the proposed approach significantly outperforms the existing proxy-based approaches.

Keywords

Ad Hoc Networks, Cooperative Cache, Cache Management, Cache Replacement Policy, Simulations. Nearest Neighbor Query, Window Query, Spatial Query Processing, Location-based Service.

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C. Gopala Krishnan ¹, V. Kavitha ¹, J. Jesu Vedha Nayahi ¹

Affiliations
1 Department of Computer Science, Anna University, Tirunelveli-07, IN

Abstract

Broadcast Queries (BQs) refer to spatial queries whose answers rely on the location of the inquirer. Efficient processing of BQs is of critical importance with the ever-increasing deployment and use of mobile technologies. Novel approach is based on peer-to-peer sharing, which enables us to process queries without delay at a mobile host by using query results cached in its neighboring mobile peers. We design and evaluate cooperative caching techniques to efficiently support data access in ad hoc networks. We first propose two schemes: Cache Data, which caches the data, and Cache Path, which caches the data path. After analyzing the performance of those two schemes, we propose a hybrid approach (Hybrid Cache), which can further improve the performance by taking advantage of Cache Data and Cache Path while avoiding their weaknesses. Cache replacement policies are also studied to further improve the performance. Simulation results show that the proposed schemes can significantly reduce the query delay and message complexity when compared to other caching schemes.

Keywords

Ad Hoc Networks, Cooperative Cache, Cache Management, Cache Replacement Policy, Simulations.

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