Explain the concept of WPAN (Wireless personal area network).
A WPAN(wireless personal area network) is a personal area network - a network for interconnecting devices centered around an individual person's workspace - in which the connections are wireless.
A key concept in WPAN technology is known as plugging in. In the ideal scenario, when any two WPAN-equipped devices come into close proximity (within several meters of each other) or within a few kilometers of a central server, they can communicate as if connected by a cable.
Another important feature is the ability of each device to lock out other devices selectively, preventing needless interference or unauthorized access to information.