AirPort Extreme Base Station (2009 model) full review
Think back to the first time you saw a computer accessing the Internet wirelessly. (Yes, kids, there was a time before Wi-Fi). It totally blew your mind, didn’t it? Since then, Wi-Fi base stations have become something of a commodity. The new AirPort Extreme Base Station (2009 edition) might not bring that first thrill of wonder back to Wi-Fi, but it certainly crams an incredible amount of power into a tiny, low-price box.
There are two different kinds of newness in the Airport Extreme: firmware (software) and hardware. On the firmware front, Apple has added the ability to connect over the Internet to any drive plugged into the USB port on the back of the AirPort Extreme. (Both current and previous-generation AirPort Extremes get this new feature.)
Simply enter your MobileMe credentials in the MobileMe preference pane on the Airport Extreme (a MobileMe account is required for this feature; be aware that an email-only MobileMe account won’t get you Back to My Mac functionality) and you can access the attached drive via any Mac running Leopard that has Back to My Mac enabled with that same MobileMe account.
In my testing, this feature worked well, but is highly dependent on the network conditions. A tightly controlled network (in an office, say) might have the ports that Back to My Mac needs blocked off, but the feature should work in most public hot spots.
The hardware additions are more numerous, but you wouldn’t know it from the outside of the unit. The casing hasn’t changed a bit, nor have the ports on the back. What have changed are the radios inside. The AirPort Extreme now has two Wi-Fi radios, which enable a feature called simultaneous dual-band. Basically, the AirPort Extreme sets up two different 802.11n (Draft N) networks: a 5GHz-band network only for newer Macs, and a 2.4GHz-band network required for older devices that use 802.11b and 802.11g protocols (802.11n can use either band).
Computers, iPhones, and other devices connect to whichever network they are compatible with. That means devices which include support for the fast 5GHz-band will always use that band when appropriate.
Previous generations of AirPort Extremes included one radio that was capable of broadcasting either a 2.4GHz or 5GHz network, but not both at once. You had to make a choice to use either the 2.4GHz band, which allows devices with 802.11b or 802.11g hardware (iPhones or older Macs) to connect but achieves only a fraction of 802.11n's potential, or build two networks with one servicing 2.4GHz-only devices and the other set to 5GHz for newer 802.11n hardware.
Simultaneous dual-band works around this by having two dedicated networks, one for each band, allowing the highest speeds for every Wi-Fi adapter.