The first part of this book deals with specifying the rules of the network algorithmics game. We start with a quick introduction where we define network algorithmics and contrast it to algorithm design. Next, we present models of protocols, operating systems, processor architecture, and hardware design; these are the key disciplines used in the rest of the book. Then we present a set of 15 principles abstracted from the specific techniques presented later in the book. Part I ends with a set of sample problems together with solutions obtained using the principles. Implementors pressed for time should skim the Quick Reference Guides directly following the introduction to each chapter.