KTI Networks KGS-2416 User Manual
Page 175

171
Designated Priority:
Show the current root bridge priority.
Root Port:
Show port number connected to root bridge with the lowest path cost.
Root Path Cost:
Show the path cost between the root port and the designated port of the 
root bridge. 
Current Max. Age:
Show the current root bridge maximum age time. Maximum age time is 
used to monitor if STP topology needs to change. When a bridge does 
not receive a hello message from root bridge until the maximum age time 
is counted down to 0, the bridge will treat the root bridge malfunctioned 
and issue a Topology Change Notification (TCN) BPDU to all other 
bridges. 
All bridges in the LAN will re-learn and determine which the root bridge is. 
Maximum Age time is assigned by root bridge in unit of seconds. Default 
is 20 seconds. 
Current Forward Delay:
Show the current root bridge forward delay time. The value of Forward 
Delay time is set by root. The Forward Delay time is defined as the time 
spent from Listening state moved to Learning state or from Learning 
state moved to Forwarding state of a port in bridge. 
Hello Time:
Show the current hello time of the root bridge. Hello time is a time 
interval specified by root bridge, used to request all other bridges 
periodically sending hello message every “hello time” seconds to the 
bridge attached to its designated port. 
STP Topology Change Count:
STP Topology Change Count expresses the time spent in unit of seconds 
since the beginning of the Spanning Tree Topology Change to the end of 
the STP convergence. Once the STP change is converged, the Topology 
Change count will be reset to 0. The figures showing in the screen may 
not be the exact time it spent but very close to, because the time is 
eclipsing. 
Time Since Last Topology Change:
Time Since Last Topology Change is the accumulated time in unit of 
seconds the STP has been since the last STP Topology Change was 
made. When Topology Change is initiated again, this counter will be 
reset to 0. And it will also count again once STP topology Change is 
completed. 
