Wireless PAN systems generally apply to individual users, and some offer support for multiple users. Take a closer look at several wireless PAN system configurations.
Many different system configurations of wireless PANs exist in the home and small office.
One of the most common uses of wireless PANs is PDA and cell phone synchronization with a laptop or PC. Figure 4-3 illustrates the interconnection of components for this type of system. When the user presses a sync button on the handheld device, the radio NIC within the handheld device sends the corresponding data to the radio NIC in the laptop or PC. Likewise, the laptop or PC will send data to the handheld device. In most cases, the wireless connection extends the serial RS-232 port wirelessly to the handheld device.
A large number of wireless PAN applications involve streaming audio and video. For example, a user can easily listen to streaming MP3 files stored on an MP3 player. (See Figure 4-4.) Many PDAs have the capability of playing MP3 audio files by installing one of the popular media players, such as the RealOne media player from RealNetworks, Inc. With a wireless PAN, the user doesn't need to carry around the MP3 player and mess with wires or stay within the same area to listen to music. A similar configuration involves the use of a wireless audio earpiece and microphone for a hands-free operation of a cell phone. A drawback to this approach, however, is that batteries will not last as long when using the wireless connections.
Another benefit of wireless PANs in streaming applications is flexible connectivity between video cameras and a server. A homeowner could, for example, place web cams in strategic places for security monitoring purposes. A hidden camera aimed at the front door area allows the homeowner to screen visitors before opening the door. The use of wireless, in this case, simplifies the installation because it eliminates the need to run wires to the camera. Electrical current or batteries are still necessary to power the camera, of course, but electrical outlets are available throughout a home.
Wireless PANs eliminate wires for computer peripherals, such as a wireless mouse, keyboard, and telephone connection, making it easier to move and set up PCs. A user, for example, can use a full-sized keyboard wirelessly with a laptop or PDA. In addition, wireless PANs reduce the tangle of cables surrounding a desktop computer. Reliability is higher because of less cable breakage and less risk of someone inadvertently kicking a cable loose.
Wireless connections between your PC and printer are made possible within the same room through a wireless PAN connection. (See Figure 4-5.) Printer cables are often too short, and you're stuck setting the printer in a less than ideal location. The wireless PAN connection allows the movement of the printer to a better location.
A user can access e-mail and browse the web from anywhere within the room with a wireless PAN interface to the Internet. Instead of sitting at a desk, for example, a person can relax in a lounge chair or couch. This freedom makes computing much more enjoyable. Figure 4-6 shows the system configuration that makes this possible.
The use of wireless PANs in enterprise is common; however, the applications and system configurations are similar to homes and small offices. Employees use wireless PANs to synchronize PDAs with desktop computers and take advantage of wireless peripherals. Instead of using a wireless PAN router for connecting users to the Internet however, an enterprise makes use of wireless LANs for Internet connectivity. Enterprises span too large of an area to make wireless PANs practical because of the rather large number of required base stations.