What are the technical disadvantages with WPA2?
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The only disadvantage of WPA2 (when comparing to WPA) is in the amount of processing power that it needs in order to protect your network. This translates to a direct need for more powerful hardware or suffer a reduction in network performance for heavily used networks. This is an issue with older access points which were designed and built prior to WPA2 and only implemented WPA2 via a firmware upgrade. Most of the more recent access points have been equipped with more capable hardware to minimize the speed degradation.