Specifications

Waters Network Systems 2800M/MR User’s Manual Page 72
When the GSM switch is the root bridge, the whole LAN will apply the number set by the switch
as their maximum age time. When a bridge received a BPDU originating from the root bridge
and if the message age conveyed in the BPDU exceeds the Max. Age of the root bridge, the
bridge will treat the root bridge as malfunctioning and issue a Topology Change Notification
(TCN) BPDU to all other bridges. All bridges in the LAN will re-calculate to determine who the
root bridge is. The valid value of Max. Age is 6 ~ 40 seconds. Default is 20 seconds.
Forward Delay:
You can set the root bridge forward delay time. This figure is set by the root bridge only. The
forward delay time is defined as the time spent from Listening state moved to Learning state
and also from Learning state moved to Forwarding state of a port in bridge. The forward delay
time contains two states, Listening state to Learning state and Learning state to Forwarding
state. It assumes that forward delay time is 15 seconds, then total forward delay time will be 30
seconds.
The valid value is 4 ~ 30 seconds, default is 15 seconds.
Force Version:
Two options are offered for the STP algorithm. One is RSTP and the other is STP. If STP is
chosen, RSTP will run as a legacy STP. The switch supports RSTP (802.1w) which is backward
compatible with STP (802.1d).
Figure 5.36 – STP Status