Wireless networking capabilities of one form or another are built into many modern computing devices. Infrared transceiver ports have been made standardized on the computers. Wireless Ethernet and Bluetooth capabilities are increasingly popular as integrated components, or can easily be added using PCI or PCMCIA add-on cards. Figure WN-l shows a PCI card that accepts a wireless PCMCIA Ethernet card.
You can also add wireless network capabilities using external USB wireless network adapters as shown in Fig.WN-2.

Wireless network adapters are not limited to PCs. Many hand-held computers and PDAs have wireless capabilities built-in or available as add-on options.

To extend the capabilities of a wireless Ethernet network, such as connecting to a wired network or share a high speed internet connection, you need a wireless access point (WAP). A WAP centrally connects wireless network nodes in the same way as a hub connects wired Ethernet PCs. Many W APs also act as high speed switches and Internet routers.

Wireless communication via Bluetooth comes as a built-in option on newer PCs and peripheral devices, or you can add it to an older PC via an external USB Bluetooth adapter.