City University of Hong Kong
DSpace
 

CityU Institutional Repository >
3_CityU Electronic Theses and Dissertations >
ETD - Dept. of Electronic Engineering  >
EE - Doctor of Philosophy  >

Please use this identifier to cite or link to this item: http://hdl.handle.net/2031/3893

Title: Web caching systems : design and analysis
Other Titles: Wan wei wang kuai qu xi tong de she ji yu fen xi
萬維網快取系統的設計與分析
Authors: Wong, Kin Yeung (王建陽)
Department: Dept. of Electronic Engineering
Degree: Doctor of Philosophy
Issue Date: 2002
Publisher: City University of Hong Kong
Subjects: Browsers (Computer programs)
Cache memory
Software configuration management
World Wide Web
Notes: CityU Call Number: TK7895.M4 W66 2002
Includes bibliographical references (leaves 126-136)
Thesis (Ph.D.)--City University of Hong Kong, 2002
x, 136 leaves : ill. ; 30 cm.
Type: Thesis
Abstract: Web caching is widely viewed as an effective way to improve Web performance and make it scalable. In this thesis, we examine the design and analysis of Web caching systems. Initially, we propose a new basis for making caching decisions; namely, a site-based approach. Unlike the focus of conventional approaches, the essence of this approach is to consider only the Web site that an object belongs to, not the object itself. We show that this approach brings many benefits for several different types of applications in Web caching areas. Based on the idea of the site-based approach, we propose a site-based mapping scheme for parallel proxy servers. The basic idea is to map all Web objects belonging to the same site to the same proxy server. By taking advantage of the persistent connection feature provided by HTTP/1.1, this mapping scheme reduces 40%-70% of the connection setups and teardowns when compared to a traditional URL-based mapping scheme. To overcome the problem of overloaded proxy servers, we propose a site-based dispatching (SBD) technique that, by preventing unnecessary requests from reaching the proxy, reduces the workload. Analytical and simulation results show that the proposed technique reduced the proxy load by up to 48% and hence enabled a system throughput gain of up to 55%. To address the question of limited storage capacity, we study the startup behaviors of caching systems using the least-recently-used (LRU) cache replacement policy. We present exact analyses of cache occupancy and cache miss probability. These measures provide insights into know how long a cache takes to become fully occupied, and how quickly a cache reaches its acceptable cache miss probability. These analyses are proven to be very accurate by computer simulations. Finally, we discuss polling models that can be used to model many areas in Web caching systems. We present a new approximation of mean-waiting time for asymmetric polling systems with nonexhaustive service discipline. Numerical results show that our proposed method gives a more reliable and accurate result than those of another well-known approximation.
Online Catalog Link: http://lib.cityu.edu.hk/record=b1761549
Appears in Collections:EE - Doctor of Philosophy

Files in This Item:

File Description SizeFormat
fulltext.html157 BHTMLView/Open
abstract.html157 BHTMLView/Open

Items in CityU IR are protected by copyright, with all rights reserved, unless otherwise indicated.

 

Valid XHTML 1.0!
DSpace Software © 2013 CityU Library - Send feedback to Library Systems
Privacy Policy · Copyright · Disclaimer