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Bandwidth


Bandwidth
4.1.8 This page will describe bandwidth, which is an extremely important concept in networks.


Two types of bandwidth that are important for the study of LANs are analog and digital.

Analog bandwidth typically refers to the frequency range of an analog electronic system. Analog bandwidth could be used to describe the range of frequencies transmitted by a radio station or an electronic amplifier. The unit of measurement for analog bandwidth is hertz (Hz), the same as the unit of frequency.

Digital bandwidth measures how much information can flow from one place to another in a given amount of time. The fundamental unit of measurement for digital bandwidth is bps. Since LANs are capable of speeds of thousands or millions of bits per second, measurement is expressed in kbps or Mbps. Physical media, current technologies, and the laws of physics limit bandwidth.

During cable testing, analog bandwidth is used to determine the digital bandwidth of a copper cable. The digital waveforms are made up of many sinewaves (analog waves). Analog frequencies are transmitted from one end and received on the opposite end. The two signals are then compared, and the amount of attenuation of the signal is calculated. In general, media that will support higher analog bandwidths without high degrees of attenuation will also support higher digital bandwidths.

This page concludes this lesson. The next lesson will discuss signals and noise. The first page describes copper and fiber optic cables.

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