This work aims to provide students related to engineering careers the understanding of several issues related to data communication in networks. Not only approaches basic fundamental principles for understanding technology design, but it also provides a detailed discussion of the latest developments by presenting, whenever possible, practical examples related to these issues and considering the important underlying challenges behind every practical solution. Throughout this text the challenges of data communication in networks are analyzed, while including, technological aspects of implementation, details of standardization through protocols and practical examples for better understanding.