Unfortunately, it depends. If you simply want to allow people outside to access the network via a wireless connection, the 1300 series AP is the way to go. It can also function as a wireless bridge to link up another building. The 1400 series AP is used for building to building links, but not individual clients can associate to it. Only other AP’s. There is also a third option in using the 1500 series AP’s. These are geared towards mesh operations, so depending on your specific outdoor needs, you could use those. They use the 2.4GHz radios(802.11b/g) for the client access and 5GHz(802.11a) for the backhaul channel used between the AP’s themselves.