COMPANY CONFIDENTIAL
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3.1.2 Radio Configuration
As part of the WLAN bringup script, several environmental variables need to be set to configure the radio.
Most have default settings that are defined in Table 2 AP Environmental Variable
The most important environmental variable for radio configuration is the channel mode setting. The Access Point can
operate in several modes. The selection of the mode is generally made using the AP_CHMODE and AP_CHMODE_2
environmental variables. These are Radio level configuration parameters. Thus AP_CHMODE_2 is only valid for dual
concurrent configurations. There are three major modes: Legacy mode, 11n Static HT 20 mode, and 11n HT 20/40
mode. Channel Bandwidth is selected by the corresponding mode are also indicated by the mode value. The following table
shows the corresponding configuration for each channel mode.
Table 12 Channel Mode Parameters
Mode Type
Name
Band
Channel
Bandwidth
Legacy 11B
2.4
GHz
10
MHz
11G
2.4 GHz
10 MHz
11n HT 20
11NGHT20
2.4 GHz
20 MHz
11n HT 40
11NGHT40PLUS
2.4 GHz
40 MHz
11NGHT40MINUS
2.4 GHz
40 MHz
Note that if the channel is set to HT 40 mode, it still can support “lower” mode, e.g. stations requesting HT 20 channel
support can associate at the HT 20 rates, and so on. Thus the HT 40 mode will support both HT 20 an Legacy rates also.
3.1.3 Operating Mode
The operating mode of the AP controls the major features that are available on the AP. To select the operating mode, the
environmental variable AP_STARTMODE must be configured. The available starting modes are defined here.
Table 13 Starting Mode Parameters
Mode Description
standard
Starts a single VAP on a single radio.
rootap
Configures a VAP as a root WDS VAP. See section 3.5 for details
client
Configures the AP to operate as a remote WDS client. Used for
implementing WiFi bridge between two Ethernet subnets. See
section 3.5 for details
repeater
Configures the AP to operate as a remote WDS repeater.. Used to
extend the BSS area with the same SSID for transparent roaming..
See section 3.5 for details
multi
Multiple BSS on the same radio. See section 3.4 for details
dual
Multiple BSS with Dual concurrent radios. See section 3.6 for
details.
