The Linux operating system is gaining increasing popularity and is particularly important in the online community as a system for many servers. This new edition of volume 3, which uses Linux, is aimed at programmers who want to understand how to create web applications. In general, it examines the question "How does application software use the TCP/IP protocol to communicate over the internet?" The text focuses on the client-server example and examines algorithms for the client and server components of a distributed program. It presents an implementation that demonstrates each design and examines techniques, including application-level gateways and tunneling. Additionally, it examines various standardized application protocols and uses them to present the algorithms and implementation techniques. [...] (from the book's preface)