D-Link DAP-1155 User Manual page 23

Section 3 - Configuration
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.
Visibility Status: Check the box if you do not want the SSID of your wireless network to be broadcasted by the DAP-1155. If checked, the SSID of the
DAP-1155 will not be seen by Site Survey utilities so your wireless clients will have to know the SSID of your DAP-1155 in order to
connect to it.
Security Mode: Refer to page 65 for more information regarding the wireless security.
D-Link DAP-1155 User Manual 23