Cisco Cisco Aironet 340 Ethernet Bridges Guia Do Utilizador

When a repeater associates to a root unit data is usually transmitted 
between the units at the highest rate that they both support. The units 
may also downshift to use lower common rates if conditions warrant it.

The basic rates option is set on the root bridge. It is the set of rates that 
all nodes in the radio cell must support or they will not be allowed to 
associate.

The lowest basic rate is use to transmit all broadcast and multicast traf-
fic as well as any association control packets. Using the lowest rate 
helps ensure they will be received by all nodes even at the farthest dis-
tances.

The highest basic rate determines the maximum rate at which an 
acknowledge packet may be transmitted.

The actual frequency allowed depends on the regulatory body that con-
trols the radio spectrum in the location in which the unit is used. If the 
setting is left as “auto”, the unit will sample all the allowed frequencies 
when it is first started and try to pick one that is not in use.

This setting is only allowed on the root unit as it is in charge of setting 
up the radio cell

Since the radio link between bridges can be quite long, the time it takes 
for the radio signal to travel between the radios can become significant. 
This parameter is used to adjust the various timers used in the radio pro-
tocol to account for the extra delay.

The parameter is only entered on the root bridge, which will tell all the 
repeaters. It should be entered as the distance in kilometers of the long-
est radio link in the set of bridges.