A First Course to Network Coding/Communication Model and Network Concepts

Abstract
In this chapter, we lay the basics in communication model and network, so that readers have a big picture in mind when we go on to study the components of communication. First we introduce the Shannon-Weaver model of communication. Secondly, we introduce a network, including relevant concepts and definitions, performance measure, etc.

Abbreviations and Acronyms
Communication is a very broad subject. It involves the information to be shared, the means to do so (such as talking, composing a melody, texting), the mechanism of error correction, and so on so forth. In this book, we refer to communication in an engineering sense: communication is the process of transmitting information. To study communication, it is essential to simplify the process of communication to an easily understandable model, and quantify the components. In [2], Shannon and Weaver developed a very well-known model of communication that has since taken after their names. This model contains six major components:


 * 1) Information source, which produce a message;
 * 2) Transmitter, which converts the message into forms that are suitable for transmission: an e-mail, for instance, translate a message into a digital stream of ‘1’s and ‘0’s that can be sent via internet;
 * 3) Channel, through which the message is conveyed. It could be a physical connection, like a landline, or a logical one, like one you establish when you call someone and they pick up;
 * 4) Receiver, which reconstruct the original message from the transmitted data;
 * 5) Destination, where the message arrives;
 * 6) Noise source, a dysfunctional, yet important element of communication: it interferes with the data during transmission and makes it difficult to reconstruct the original message.