Framework to Model User Request Access Patterns in the World Wide Web

In this paper, we present a novel approach to model user request patterns in the World Wide Web. Instead of focusing on the user traffic for web pages, we capture the user interaction at the object level of the web pages. Our framework model consists of three sub-models: one for user file access, one for web pages, and one for storage servers. Web pages are assumed to consist of different types and sizes of objects, which are characterized using several categories: articles, media, and mosaics. The model is implemented with a discrete event simulation and then used to investigate the performance of our system over a variety of parameters in our model. Our performance measure of choice is mean response time and by varying the composition of web pages through our categories, we find that our framework model is able to capture a wide range of conditions that serve as a basis for generating a variety of user request patterns. In addition, we are able to establish a set of parameters that can be used as base cases. One of the goals of this research is for the framework model to be general enough that the parameters can be varied such that it can serve as input for investigating other distributed applications that require the generation of user request access patterns.

Research and Realization of the Role-Based System Access Control Management

The systematical structure of the role-based access control was analyzed,giving a full description of the definitions of user,user access,and the relation between post role and access. It puts forward a role-based access control management which is relatively independent in the applied system. This management achieves the control on user's access by distribution and cancel of role-play,which is a better solution to the problems of the access control management for the applied system. Besides,a complete scheme for the realization of this access control was provided.

Research on Semantic and Cache Model of Relational Database

The paper firstly analyze cache replacement strategies at present, and proposed the ideas of the semantic query cache replacement based on user access features, and describe the semantic similarity calculation and realize the algorithm of replacement strategy. The strategy use semantic to match information in the query cache, through dynamic analysis and tracking three characteristics of user access time, user access to content and Business Association, give out the similarity minimum of the cache item, to improve the hit ratio of the cache and the response time and throughput of the server is improved.

Design and realization of indoor VLC-Wi-Fi hybrid network

Indoor wireless communication networking has received significant attention along with the growth of indoor data traffic.VLC(Visible Light Communication)as a novel wireless communication technology with the advantages of a high data rate,license-free spectrum and safety provides a practical solution for the indoor high-speed transmission of large data traffic.However,limited coverage is an inherent feature of VLC.In this paper,we propose a novel hybrid VLC-Wi-Fi system that integrates multiple links to achieve an indoor high-speed wide-coverage network combined with multiple access,a multi-path transmission control protocol,mobility management and cell handover.Furthermore,we develop a hybrid network experiment platform,the experimental results of which show that the hybrid VLC-Wi-Fi network outperforms both single VLC and Wi-Fi networks with better coverage and greater network capacity.

Replacement Policy for Caching World-Wide Web Documents Based on Site-Graph Model

The hit rate, a major metric for evaluating proxy caches, is mostly limited by the replacement strategy of proxy caches. However, in traditional proxy caches, the hit rate does not usually successfully predict how well a proxy cache will perform because the proxy cache counts any hit in its caching space which has many pages without useful information, so its replacement strategy fails to determine which pages to keep and which to release. The proxy cache efficiency can be measured more accurately using the valid hit rate introduced in this paper. An efficient replacement strategy based on the Site Graph model for WWW (World Wide Web) documents is also discussed in this paper. The model analyzes user access behavior as a basis for the replacement strategy. Simulation results demonstrate that the replacement strategy improves proxy cache efficiency.