In metropolitan areas, it is possible to have third-party interference from
other companies that are using wireless devices. This is shown in Figure
. In this
situation, it is important to ensure that different channels are utilized.
However, this situation will not be known, until the user actually implements
the wireless link. Changing channels is the best way to avoid interference.
Remember that the 802.11 standard uses the unlicensed spectrum and, therefore,
anyone can use these frequencies.