If the Wi-Fi network you connect your Barnes & Noble Nook ereader to uses MAC address filtering, you may need to find out what the Wi-Fi MAC Address to the device is. The MAC address is a unique identifier for networking hardware. Almost all hardware made that interfaces with a network has one.
Obtaining the MAC address for your Nook is easy. Just tap the n below the screen to get to the Home screen, then tap the Settings icon. A screen will be displayed with the information you need.