Communication Systems Principles Using MATLAB

4Internet Protocols and Packet Delivery Algorithms

4.1 Chapter Objectives

This chapter examines the defined standards and methods for Internet data communications, the protocols. This encompasses the data formats employed as well as the algorithms that operate on that data in order to facilitate data communication between physically separate devices. On completion of this chapter, the reader should:

1. Be able to define IP, TCP, and UDP, the role of protocol layers, and what functions they perform.
2. Be conversant with the key elements of each protocol, such as IP addresses and TCP sockets.
3. Be able to explain potential pitfalls in networking, such as congestion collapse, and know the approaches used to mitigate these problems.
4. Be able to explain the principles of routing and calculate the shortest path in a routing graph.

There is a vast range of detail concerning the Internet protocols that cannot be discussed in detail in one chapter – the intent here is to explain the salient points and examine some important aspects in depth. In addition to Internet standard RFC documents, a very approachable reference is Kozierok (2005). Detailed explanations of the inner workings of TCP/IP are given in Stevens (1994), while implementation details are covered in Wright and Stevens (1995a).

4.2 Introduction

Suppose we wish to connect a number of devices together for the purposes of exchanging data. What is the best way to do this? What do we mean by “best” in this context? We might want ...