Ed Tittel 
Schaum’s Outline of Computer Networking [PDF ebook] 

Schaum’s Outline of Computer Networking introduces the underlying concepts, principles, and terminology of computer networks. Covering the full scope of material taught in computer networking courses, this problem-solved approach presents the different components of a network and shows how these components fit together as well as explaining the varied harmonizing functions needed for the interconnection of many heterogeneous computer networks.