D-Link DIR-615 User Manual page 33

Secton  - Configuraton
Channel Width: Select the Channel Width:
Auto.20/40 - Select if you are using both 802.11n and non-802.11n wireless devices.
20MHz - Select if you are not using any 802.11n wireless clients. This is the default setting.
Visibility Status:
Select Invisible if you do not want the SSID of your wireless network to be broadcasted by the DIR-615. If Invisible is selected,
the SSID of the DIR-615 will not be seen by Site Survey utilities so your wireless clients will have to know the SSID of your
DIR-615 in order to connect to it.
Wireless Security:
Refer to page 78 for more information regarding wireless security.
D-Lnk DIR-615 User Manual