Excerpts

Preface There are not many books written about content switching and all the associated applications that make up this exciting technology. The reason for this we believe is twofold. First, content networking is a huge discipline with many different areas ranging from switching to caching and content routing, and this can often be seen as confusing. Second, there is a perceived shortage of skills in the marketplace. While content networking does cover many areas, they are all still inextricably linked with the existing technologies of today. They might have dedicated hardware, more feature-rich software, and allow for unconventional configurations, but ultimately they come back to existing technology with which we are all familiar. On the skills and understanding front there is no shortage or lack of knowledge. Content networking is merely an extension to those existing skills we have developed. Taking the time to dig deeper into the workings of a content switch and understanding how the applications work provides the foundation on which we can build our knowledge. Using our existing knowledge, however, is key to content networking. This book does not try to explain every aspect associated with content networking as a whole, but rather it covers what is called content switching and discusses the associated applications. The Audience and Purpose of This Book The purpose of this book is to eliminate the confusion and conflicting views about this expanding topic and ensure that the fundamental theory and technologies are presented in a clear and concise manner. This is done in a two-tier approach. Managers, sales personnel, and executive-level individuals who require an overall understanding of this new breed of networking will be able to get an introductory overview of the topics involved. This will provide them with insight into the benefits and pitfalls of each application; why the need for such things as Secure Sockets Layer (SSL) offload, firewall load balancing, Web cache redirection, and so forth is a definite requirement for technology scaling; and the ability to understand the concepts of a technology that is continually changing. In short, this book will provide the individual with the basics of content switching, allowing them to make informed decisions in their day-to-day tasks and allow the sales and marketing personnel the ability to better position and sell these products. For the engineering force, this book will provide a comprehensive explanation of the inner workings of content switching, allowing them to build on their Layer 2 and Layer 3 skills. A good understanding of Layer 2 and Layer 3 functionality will ensure that the individual benefits from the advanced topics in this book. These include TCP/IP flows and sessions, delayed binding, URL/URI parsing, cookie persistence, server health checking, and load-balancing metrics, among others. Any engineers exposed to these technologies will find that the material allows them to fully understand the core concepts and functionality behind the applications discussed, giving them a better understanding of what is happening "under the hood." Case Studies As we progress through this book we will discuss fictitious case studies that revolve around a company called Foocorp, Inc. Foocorp, Inc. is a typical large company. They have thousands of employees, located in the head office and also in remote branches. The employees need access to internal applications and systems. Foocorp has also extended its network to include access from its partners and customers over an extranet. Foocorp also has an online presence for e-commerce. We will explain the benefits, the design, and the issues faced by Foocorp Inc. Excerpted from Optimizing Network Performance with Content Switching: Server, Firewall and Cache Load Balancing by Matthew Syme, Philip Goldie All rights reserved by the original copyright owners. Excerpts are provided for display purposes only and may not be reproduced, reprinted or distributed without the written permission of the publisher.