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Cache prefetching technique can improve the hit ratio and expedite users visiting speed. Predictive Web prefetching refers to the mechanism of deducing the forth coming page accesses of a client based on its past accesses.Congestion in Network remains one of the main barriers to the continuing success of the Internet. For Web users, congestion manifests itself in unacceptably long response times. One possible remedy to the latency problem is to use caching at the client, at the proxy server, or within the Internet. However, Web documents are becoming increasingly dynamic, which limits the potential benefit of caching. The performance of a Web caching system can be dramatically increased by integrating document prefetching into its design. Although prefetching reduces the response time of a requested document, it also increases the network load, as some documents will be unnecessarily prefetched.In the paper, we developed a Stair-Case prune algorithm to mine popular with their conditional probabilities from the proxy log, and stored them in the rule table. Then, according to contents and the rule table, a prediction is calculated in some precondition. After the simulation, we found that our approach has much better performance than the other ones, in terms of hit ratio. [ABSTRACT FROM AUTHOR]

Scalable and interoperable security management has become an important issue in advanced datacenter services. In our previous work, we had developed integrated access control manager (IAM) that manages accesses to various resources. To integrate access controls for various resources, a scalable and interoperable resource information service that provides target resource information to compose access control policies is required. To improve interoperability and performance of the resource information service, we brought a resource information cache into the IAM and introduced an automatic cache update control method that updates cached information proactively based on WS-Management and CIM standards. To reduce server loads to update cached information, the proposed method selects a part of cached information by content priority as an update target instead of updating all cached contents. We evaluated the average query response time of resource information service by simulating the proposed method. The proposed method reduced average query response time by 66.66% compared to the conventional reactive update control method. [ABSTRACT FROM AUTHOR]

Nowadays there is a large number of Expert Systems available to users requiring the extraction of data relevant to specific domains, many of which are based on reasoning and inference. However, many of these tools offer slow execution time, resulting in delayed response times to the queries made by users. The strategy of caching to define specific patterns of results enables such systems to eliminate the requirement to repeat the same queries, speeding up the response time and eliminating redundancy. This paper proposes a caching strategy for an Expert System based on Semantic Web and reasoning and inference techniques. Caching strategies have previously been applied to simple XML queries. Performance has been evaluated using an existing system for medical diagnosis, which demonstrates the increased efficiency of the system. [ABSTRACT FROM AUTHOR]

Peer-to-peer systems use redundant data replicas to maintain high availability and improve on user response times. The consistency and coherency of these data replicas need to be maintained over time in face of various system changes like node joins, failures and network outages. In this paper we present a robust approach to guarantee eventual coherency of replicas in a multi-location large scale peer-to-peer distributed file system. We use a combination of data pull and push mechanisms, and a last coherent time stamp on each replica. These mechanisms ensure that no user read operation ever retrieves data that is older than a configurable upper bound in time. [ABSTRACT FROM AUTHOR]

Given a query tuple q, the dynamic skyline query retrieves the tuples that are not dynamically dominated by any other in the data set with respect to q. A tuple dynamically dominates another, w.r.t. q, if it has closer to q΄s values in all attributes, and has strictly closer to q΄s value in at least one. The dynamic skyline query can be treated as a standard skyline query, subject to the transformation of all tuples΄ values. In this work, we make the observation that results to past dynamic skyline queries can help reduce the computation cost for future queries. To this end, we propose a caching mechanism for dynamic skyline queries and devise a cache-aware algorithm. Our extensive experimental evaluation demonstrates the efficiency of this mechanism compared to standard techniques without caching. [ABSTRACT FROM AUTHOR]

Caching dynamic web content is an effective approach to reduce Internet latency and server load. An ideal caching solution is one that can be added transparently by the developers and provides complete consistency of the cached documents, while minimizing false cache invalidations. In this paper, we design and implement AutoWebCache, a middleware system for adding caching of dynamic content transparently to J2EE server-side applications having a backend database. For this purpose, we first present the principles involved in caching dynamic web content, including our logic to ensure consistency of the cached entries. Thereafter, we demonstrate the use of aspect-oriented (AOP) techniques to implement our system, showing how AOP provides modularity and transparency to the entire process. Further, we evaluate the effectiveness of AutoWebCache in reducing response times of applications, thereby improving throughput. We also analyze the transparency of our system for a general application suite, considering issues such as dynamic web pages aggregating data from multiple sources, presence of insufficiently structured interfaces for exchanging information and the use of application semantics while caching. We use two standard J2EE web benchmark applications, RUBiS and TPC-W, to conduct our experiments and discuss the results obtained. [ABSTRACT FROM AUTHOR]