Background and Identification
The 2nd generation Airport Extreme Base Station (Model Number A1143) is a wireless access transmitter. The 2nd generation was released on March 19, 2008 with the addition of a new firmware update by Apple. Because each generation of Airport Extreme look so similar, it is recommended to verify your model by the model number located on the first line of information imprinted into the bottom rubberized pad. The first and second generation use the same model number, so to definitively verify your device, use the serial number located on the bottom left of the bottom rubberized pad in Apple's identification site (Link located in additional information).
AirPort Extreme is Wi-Fi certified for 802.11n draft 2.0 using two different frequency channels (2.4 GHz and 5 GHz). This Airport Extreme has a total of four Ethernet ports and one USB port to allow for access to an external hard drive or printer across the Wi-Fi.
For troubleshooting problems, see Apple AirPort Extreme Model A1143 Troubleshooting.
For the official manual by Apple for more information on setup and utilities of the AirPort Extreme, follow this link: Apple AirPort Extreme Base Station Manual
For general information the Wikipedia is very helpful:
Apple serial number verify site: