Bridge GUI Guide: Network Configuration
69
signal the impending change and transmit the new channel
number to the network, before switching its bridging radio to
the new channel. Bridges receiving this transmission will do the
same, until the new channel has been propagated to every
Bridge in the network and all are all connected over the new
channel.
NOTE:
Radios us-
ing DFS channels
must
use the default
Beacon Interval
of
100
If you manually change the
Channel
setting on a bridging radio
(Section 3.3.2.3), the new channel will be propagated to the
rest of the network in the same manner.
You can observe the view-only
actual
channel on
Configure
->
Radio Settings
, to the right of the
Channel
setting (which persists
as specified as the
actual
channel changes).
3.3.3.2
Channel Exclusion
For each enabled radio, Fortress Bridges maintain a list of
channels excluded from that radio’s use, Channels that are
unavailable for DFS or for manual selection. Bridging radios in
a mesh network maintain a global list of excluded channels by
propagating their channel exclusions to all nodes.
Figure 3.9. Advanced View
DFS Channel Exclusions
list, all radio-equipped platforms
Channels can be excluded in four ways:
The channel was manually added to the radio’s excluded
list (see below).
NOTE:
While there
can be no radar
events on 4.4 GHz mili-
tary band radio, it can
receive a remote chan-
nel change from a net-
work peer.
For DFS channels, a radio using the channel detected
radar and had to change to a different channel. The
channel on which radar was detected is excluded from use
for 30 minutes, after which it will automatically become
available again.
For bridging radios, the channel was learned remotely from
another node in the network. Remotely learned channel
exclusions will age out a radio’s excluded list if the remote
Bridge stops propagating the exclusion (or drops out of the
network).
For multi-radio Bridges, the channel is in use by the other
radio internal to the Bridge and so is excluded from use by
the current radio.
You may want to exclude a channel from use if you are
experiencing abnormal interference on the channel, for
example, or in order to avoid a channel on which intermittent
radar is known to take place.
