Did you read the doc I provided earlier ? Most of those questions are answered there
https://www.arubanetworks.com/assets/so/SG_IAP-VPN.pdfYes , all those are possible with an IAP.
IAPs have a built in firewall so you prioritize certain traffic like VoIP.
Based on the AP you purchase you can provide wired network connectivity to local devices (303H , 505H) provide additional ports
Thank you
Victor Fabian
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