The campus at large supports several incarnations of WIFI access, with the newest standards always exceeding the performance of the older ones. The buildings recently built (or extensively renovated) support the latest commonly available wireless network standard known as 802.11ac. Several buildings support the 802.11n standard (in both the 2.4 and 5 Ghz frequency ranges). There are still yet other buildings which only support 802.11a and 802.11b/g. Fortunately, devices with the latest standard (802.11ac) also support the older generations of WIFI; and older devices can be used in the new buildings, but obviously in both of these cases, the performance will be less than optimal. There is a good chance that purchasing a device today will have the latest standard, 802.11ac as part of the feature set, which will provide the best performance in buildings that support 802.11ac.
As noted above, if you have a device which supports 802.11n, you may not get the performance you may have expected. 802.11n is available in two spectrums or ranges of wireless frequencies (2.4 GHz and 5.4-5.8 GHz). The 2.4 GHz range was the original standard for wireless and is far more crowded than the 5.4-5.8 GHz range. Some vendors were selling 802.11n devices that only supported the 2.4 GHz range. However, if you want the best throughput on our campus wireless system in locations that have not yet been upgraded to 802.11ac, you should use a network card that supports both 2.4 GHz and 5.4-5.8 GHz ranges. A quick way to tell is to look for a card that says it supports 802.11 a/b/g/n (or 802.11 a/g/n).