Network Media

Communication across a network is carried on a medium. The medium provides the channel over which the message travels from source to destination.
Modern networks primarily use three types of media to interconnect devices and to provide the pathway over which data can be transmitted. As shown in Figure 1, these media are:

• Metallic wires within cables - data is encoded into electrical impulses

• Glass or plastic fibers (fiber optic cable) - data is encoded as pulses of light

• Wireless transmission - data is encoded using wavelengths from the electromagnetic spectrum

Different types of network media have different features and benefits. Not all network media have the same characteristics, nor are they all appropriate for the same purpose.
Figure 2 displays criteria to consider when choosing network media.