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Another aspect of WAN technologies that can have a big effect on the speed, bandwidth, and the volume of data that can be transferred is the type of transmission media. Wireless transmissions use air as a transmission media. This not only creates a bit of challenge concerning security, it also presents us with signal degradation—the further the signal has to travel from the original source, the weaker it gets. A solution to this last hang-up comes through using microwave repeaters that retransmit signals through the air and bolster them. This approach is a lot more efficient because it can preserve signal strength over much greater distances.
The most far-reaching technology uses the air and even empty space to send electromagnetic signals to satellites from which they are then resent to distant geographic locations.