The World Wide Web (WWW) can be characterized as one of the greatest achievements of information technology. Its phenomenal expansion is the result of significant advances in many areas of computer science research, including networking, hypermedia systems, human-computer interaction, and distributed systems. Its success has transformed the Web into a limitless source of new and challenging research problems and areas, ranging from graph theory, algorithms, and information retrieval to network programming and Web mining. Furthermore, its rising popularity since the mid-90s has made it the topic of numerous new books seeking to tackle various aspects of Web technology, including HTML and Web publishing, TCP/IP networking, client- and server-side scripting, Web servers, XML, Java, and e-commerce. Courses on Web technologies have gradually been introduced into computer science curricula around the world, at an introductory level, providing practical competencies; at an advanced undergraduate level, covering technologies underlying the WWW; and at a graduate level, focusing on some of the research topics that arise in the scope of the Web.
Arguably, for all these books and courses, the Web represents a moving target. The presentation of the Web’s technical underpinnings is a very challenging endeavor because of its rapid growth. Every year, new applications are deployed, technologies and systems appear, and new usage patterns emerge. Consequently, it is not difficult to understand why CS curricula regarding Web technologies typically rely either on rather superficial technical books that explain how to use particular tools and technologies without trying to examine the design philosophy of the WWW, or on papers from research literature and technical notes from the World Wide Web Consortium (W3C) and the Internet Engineering Task Force (IETF).
This book represents one of the first successful efforts to address this challenging topic and provide a reference, with an integrated, comprehensive, and in-depth study of the WWW. As the authors point out, the book focuses on “the protocols and software components involved in transferring Web content,” and avoids the discussion of topics that “may not have sufficient longevity to warrant inclusion.” This goal is achieved by the selection of appropriate topics (both introductory and more advanced), and the presentation of the different topics at an appropriate level of detail. Presentations of vendor-specific components are covered at a higher-level of abstraction, whereas issues of architecture and protocols are studied in depth. In addition, a large and carefully selected list of references to research publications is included. The organization of the book reflects this approach: the material covered is organized in six modules, spanning 13 chapters.
The first two modules, “Getting Started” and “Web Software Components,” are introductory, describing the basic structure of the WWW and its components. Topics such as Uniform Resource Identifiers (URIs), Hypertext Markup Language (HTML), and Hypertext Transfer Protocol (HTTP), are introduced, along with the principles behind the main software components of the Web (clients, servers, and proxies). Module 3 is dedicated to protocols of the WWW. The authors undertake an in-depth treatment of HTTP, following a presentation of the networking protocols underlying HTTP, such as TCP/IP, DNS, and application protocols (telnet, ftp, and so on). Two chapters are dedicated to HTTP and HTTP/1.1; the authors present the philosophy, design, evolution, and capabilities of HTTP. The next two modules of the book are dedicated to more advanced topics of the WWW: the measurement and characterization of Web traffic (module 4), Web caching, and multimedia streaming (module 5). In these chapters, the authors provide a remarkable overview of recent research results, providing references to seminal publications of relevance. Finally, module 6 presents an overview of research perspectives in Web caching, traffic monitoring and WWW protocols.
This book does not include any discussion of recent developments in Web services protocols and architectures, which deserves some coverage. There is also no substantial discussion on markup languages for the WWW (such as HTML and XML), but since this has been covered extensively elsewhere, its omission does not affect the coherence and completeness of the book.
The two authors, besides being very experienced in technical writing, have had first-hand exposure to WWW components, protocols, and relevant developments. This becomes apparent from the clarity of their text, both in the introductory and the more advanced chapters. There is a great deal of solid background knowledge here, including the detailed description of HTTP, the analysis of its interdependence with TCP/IP, and its support for Web caching, as well as the discussion of cookies and the real time streaming protocol (RTSP). This background is necessary for anyone planning to undertake the challenging patchwork of programming components that make use of--and interface with--the protocols of the Web.
The book has an important drawback as a textbook: there are no questions, suggested problems and projects, or an instructor manual that could be used to support classes adopting it. It could be used alternatively as introductory material for new researchers seeking to review the foundations and recent developments of the WWW. It could also serve as a reference guide for more experienced researchers and developers, who will find a concise and knowledgeable overview of many topics, along with adequate references to the research literature.
In conclusion, this is a very good book, one of the few that provides an integrated and in-depth study of the core technologies of the World Wide Web.
