User`s guide

8 - 8 Ethernet or Token Ring Bridge
The root Bridge in turn will include a ßag in all the conÞguration mes-
sages it sends.This ßag will be propagated through the infrastructure by
all the other Bridges. After a time period the root Bridge will clear the
ßag. This instructs all Bridges to return to the normal aging timeout.
Implementing STP Protocol
The STP protocol is implemented on the Aironet Ethernet or Token Ring
Bridge as follows.
n Each root Bridge, with all of its repeaters, looks to other Bridges in
the infrastructure as a single multi-port Bridge with a Bridge
address equal to the infrastructure address of the root Bridge.
n The STP protocol runs only on the root Bridge, not on repeaters.
Repeaters only transmit packets or change state on commands from
the root Bridge.
n To reduce radio trafÞc, the repeaters will continue to transmit con-
Þguration messages at the timeout period without having to be told
to transmit each one by the root Bridge. They will also only send
received conÞguration messages back to the root Bridge if they are
different from the previously received message.
n When a repeater is not associated to a parent Bridge, it will put its
LAN port in the blocked state and will not forward any data to or
from the port. Once associated, the root Bridge will take control.
n The protocol parameters are all conÞgured from the root Bridge.
The local port parameters are conÞgured on each repeater Bridge.