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The short answer is yes, although it varies depending on how you want to authenticate and to what do you want to have your clients authenticate. For details on how to configure your Aerohive APs as authenticators to an External RADIUS server, I would have a look at this guide to get you started. It is a very well written guide on the basics of getting RADIUS authentication up and running and should help you out. If you have any specific questions, feel free to come back and ask.