Should be WPA2/AES.
Do you have both radios enabled?

Now i don't have radius i think i don't use wpa2/aes with my clients. Do you have another solution ? .you have enough  documentation relate with this case  or do not.

Thank you.

No, no no, not RADIUS.  It's RADIOS.    You either have to use WPA2/AES or open/no authentication.

Cisco 802.11n Design and Deployment Guidelines
http://www.cisco.com/en/US/solutions/collateral/ns340/ns394/ns348/ns767/white_paper_80211n_design_and_deployment_guidelines.html

I think WPA2/AES must use authentication with radius [internal or external] don't use passkey for access with SSID. i want to use only encryption key only for access 802.11n please tell me more solution. in case open / no authen think it not secure.

thank you for best support.

You can disable broadcast SSID and enable MAC ACL for open/no authentication.

There are alot of free RADIUS programs.  Among then is FreeRADIUS.

No no.... here are your options for 802.11n Speeds...

Option 1

WPA2/AES - PRESHARE KEY

Option 2

WPA2/AES - EAP (Radius)

Option 3

OPEN

Options 4

OPEN (Mac filter / Auth)

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