Administrator Guide

613 | Access Points Dell Networking W-Series ArubaOS 6.4.x| User Guide
l Unconventional scans are no longer interspersed with conventional scans. Unconventional scans operate
with a lower frequency, because they belong to a new low priority channel type.
l Unconventional scans are performed in all-regulatory and rare scan modes. But these scans will not be
performed if the scan mode is set to regulatory domain. This modification enables the AP to scan through
active channels, regulatory channels, and all-regulatory channels faster.
Currently, W-AP200 Series access points do not support unconventional or rare channel scanning.
Modifications in Scan Frequency
A modification is introduced to increase the frequency of visits to active and regulatory domain channels.
Channel type categories are:
l DOS
l Active
l Regulatory domain
l All-regulatory domain
l Unconventional or rare
Unconventional or rare channels are merged for scanning.
Channel Group Scanning
Since a 11ac AP radio can hear frames sub-channels when it performs an 80MHz wide scan, scanning can be
optimized by categorizing channels into scan groups, which are visited sequentially when a new primary
channel is selected. This allows the AP scan through the list of channels faster, so that the delay between visits
to channels in a group is reduced.
For more information on Channel Group Scanning, see Channel Group Scanning on page 613
Channel Group Scanning
The following section describes channel group scanning:
l Channel groups can be 80MHz (4 channels), 40MHz (2 channels), or 20MHz wide (1 channel).
l Each channel is mapped to a group depending on the maximum width supported by that channel and the
radio’s capability. The maximum width supported by a channel is determined by the channel’s membership
in regulatory domain channel pairs or groups.
n Channel 36, 40, 44, and 48 belong to 80MHz group
n Channel 165 belongs to 20MHz group
l Channel groups are visited sequentially and the primary channel is rotated after each visit.
l Group scanning behavior is performed for W-AP200 Series access points on A-band channels.
Scanning only once in each 80MHz wide group allows the AP to scan through the channel list faster and also hear
frames on sub-channels.
Configuring AP Channel Assignments
The country code in the AP Regulatory Domain profile determines supported channel and channel pairs for
that specific AP. Any changes to the country code causes the valid channel lists to be reset to the defaults for