Networking Bible

Chapter 5. Bandwidth and Throughput

IN THIS CHAPTER

• Learn how signals are used to send data

• See how to store and recreate complex data

• Learn how multiple data streams can share the same connection

• Understand resource allocation and traffic control methods

Information flows over a network as a series of signals. Those signals can represent either analog or digital data. Groups of signals are defined by various standards to represent different types of data. Some groups can be character sets, and some groups might be the various notes of a song or words in a conversation. It is up to various protocols to encode and decode the data, while other protocols are responsible for transporting and controlling the flow of the data. A collection of data represents information. The bandwidth of a network segment, its throughput, and its capacity are described.

Signals that carry data are transferred in the form of periodic waves. Any periodic function or complex waveform can be described by a Fourier transform, which is a mathematical operation that takes a complex waveform and transforms it into another set of simpler sinusoidal functions and coefficients. This analysis creates a set of terms called harmonics that perform curve fitting. This process is needed to store information and recreate it later.

A waveform can be recreated by sampling the wave and splitting it into small components. Sampling theory places a limit on the amount of sampling you can do and still obtain useful information.

Multiple ...