1. Chapter 1 Introduction

   1. Web Architecture

   2. Web Transport Protocols

   3. Why Cache the Web?

   4. Why Not Cache the Web?

   5. Types of Web Caches

   6. Caching Proxy Features

   7. Meshes, Clusters, and Hierarchies

   8. Products

2. Chapter 2 How Web Caching Works

   1. HTTP Requests

   2. Is It Cachable?

   3. Hits, Misses, and Freshness

   4. Hit Ratios

   5. Validation

   6. Forcing a Cache to Refresh

   7. Cache Replacement

3. Chapter 3 Politics of Web Caching

   1. Privacy

   2. Request Blocking

   3. Copyright

   4. Offensive Content

   5. Dynamic Web Pages

   6. Content Integrity

   7. Cache Busting and Server Busting

   8. Advertising

   9. Trust

   10. Effects of Proxies

4. Chapter 4 Configuring Cache Clients

   1. Proxy Addresses

   2. Manual Proxy Configuration

   3. Proxy Auto-Configuration Script

   4. Web Proxy Auto-Discovery

   5. Other Configuration Options

   6. The Bottom Line

5. Chapter 5 Interception Proxying and Caching

   1. Overview

   2. The IP Layer: Routing

   3. The TCP Layer: Ports and Delivery

   4. The Application Layer: HTTP

   5. Debugging Interception

   6. Issues

   7. To Intercept or Not To Intercept

6. Chapter 6 Configuring Servers to Work with Caches

   1. Important HTTP Headers

   2. Being Cache-Friendly

   3. Being Cache-Unfriendly

   4. Other Issues for Content Providers

7. Chapter 7 Cache Hierarchies

   1. How Hierarchies Work

   2. Why Join a Hierarchy?

   3. Why Not Join a Hierarchy?

   4. Optimizing Hierarchies

8. Chapter 8 Intercache Protocols

   1. ICP

   2. CARP

   3. HTCP

   4. Cache Digests

   5. Which Protocol to Use

9. Chapter 9 Cache Clusters

   1. The Hot Spare

   2. Throughput and Load Sharing

   3. Bandwidth

10. Chapter 10 Design Considerations for Caching Services

    1. Appliance or Software Solution

    2. Disk Space

    3. Memory

    4. Network Interfaces

    5. Operating Systems

    6. High Availability

    7. Intercepting Traffic

    8. Load Sharing

    9. Location

    10. Using a Hierarchy

11. Chapter 11 Monitoring the Health of Your Caches

    1. What to Monitor?

    2. Monitoring Tools

12. Chapter 12 Benchmarking Proxy Caches

    1. Metrics

    2. Performance Bottlenecks

    3. Benchmarking Tools

    4. Benchmarking Gotchas

    5. How to Benchmark a Proxy Cache

    6. Sample Benchmark Results

1. Appendix Analysis of Production Cache Trace Data

   1. Reply and Object Sizes

   2. Content Types

   3. HTTP Headers

   4. Protocols

   5. Port Numbers

   6. Popularity

   7. Cachability

   8. Service Times

   9. Hit Ratios

   10. Object Life Cycle

   11. Request Methods

   12. Reply Status Code

2. Appendix Internet Cache Protocol

   1. ICPv2 Message Format

   2. Opcodes

   3. Option Flags

   4. Experimental Features

3. Appendix Cache Array Routing Protocol

   1. Membership Table

   2. Routing Function

   3. Examples

4. Appendix Hypertext Caching Protocol

   1. Message Format and Magic Constants

   2. HTCP Data Types

   3. HTCP Opcodes

5. Appendix Cache Digests

   1. The Cache Digest Implementation

   2. Message Format

   3. An Example

6. Appendix HTTP Status Codes

   1. 1xx Intermediate Status

   2. 2xx Successful Response

   3. 3xx Redirects

   4. 4xx Request Errors

   5. 5xx Server Errors

7. Appendix U.S.C. 17 Sec. 512. Limitations on Liability Relating to Material Online

8. List of Acronyms

9. Appendix Bibliography

   1. Books and Articles

   2. Request For Comments

10. Colophon

Our look is the result of reader comments, our own experimentation, and feedback from distribution channels. Distinctive covers complement our distinctive approach to technical topics, breathing personality and life into potentially dry subjects. The animal on the cover of Web Caching is a rock thrush. Rock thrushes belong to the order Passeriformes, the largest order of birds, containing 5,700 species, or over half of all living birds. Passerines, as birds of this order are called, are perching birds with four toes on each foot, three that point forward and one larger one that points backward. Rock thrushes belong to either the genus Monticola or the genus Petrocossyphus, such as Monticola solitarius, the blue rock thrush, and Petrocossyphus imerinus, the littoral rock thrush. Leanne Soylemez was the production editor and copyeditor for Web Caching. Matt Hutchinson was the proofreader, and Jeff Holcomb provided quality control. Brenda Miller wrote the index.

Edie Freedman designed the cover of this book. The cover image is a 19th-century engraving from the Dover Pictorial Archive. Emma Colby produced the cover layout with QuarkXPress 4.1 using Adobe's ITC Garamond font.

Melanie Wang designed the interior layout based on a series design by Nancy Priest. The print version of this book was created by translating the DocBook XML markup of its source files into a set of gtroff macros using a filter developed at O'Reilly & Associates by Norman Walsh. Steve Talbott designed and wrote the underlying macro set on the basis of the GNU troff s macros; Lenny Muellner adapted them to XML and implemented the book design. The GNU groff text formatter version 1.11.1 was used to generate PostScript output. The text and heading fonts are ITC Garamond Light and Garamond Book; the code font is Constant Willison. The illustrations that appear in the book were produced by Robert Romano and Jessamyn Read using Macromedia FreeHand 9 and Adobe Photoshop 6. This colophon was written by Leanne Soylemez.