Edimax Technology EW-7438RPn manual Encryption, Pre-shared Key, Channel Number

Channel Number	Channel number for the guest network is the
	same as the main SSID and cannot be adjusted
	independently.
Encryption	Enable or disable encryption for the guest
	network.
Pre-shared Key	When encryption is enabled, enter a
	pre-shared key (password) for your guest
	network.

You cannot select a different encryption type (e.g. WEP, TKIP, etc.) for your guest network. The default encryption type is WPA2 which is the most secure encryption type.

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