User Manual
Publication date: May, 2005
Revision A1
104
3-14-2. STP Configuration
The STP, Spanning Tree Protocol, actually includes RSTP. In the Spanning
Tree Configuration, there are six
parameters open for the user to configure as
user’s idea. Each parameter description is listed below.
Function name:
STP Configuration
Function description:
User can set the following Spanning Tree parameters to control STP function
enable/disable, select mode RSTP/STP and affect STP state machine
behavior to send BPDU in this switch. The default setting of Spanning Tree
Protocol is “Disable”.
Parameter description:
Spanning Tree Protocol:
Set 802.1W Rapid STP function Enable / Disable. Default is “Disable”
Bridge Priority:
The lower the bridge priority is, the higher priority it has. Usually, the
bridge with the highest bridge priority is the root. If you want to have the
GSW-1291 as root bridge, you can set this value lower than that of
bridge in the LAN. The valid value is 0 ~ 61440. The default is 32768.
Hello Time:
Hello Time is used to determine the periodic time to send normal BPDU
from designated ports among bridges. It decides how long a bridge
should send this message to other bridge to tell I am alive. When the
GSW-1291 is the root bridge of the LAN, for example, all other bridges
will use the hello time assigned by this switch to communicate with each
other. The valid value is 1 ~ 10 in unit of second.
Default is 2 seconds.
Max. Age:
When the GSW-1291 is the root bridge, the whole LAN will apply this
figure set by this switch as their maximum age time. When a bridge
received a BPDU originated 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 malfunctioned and issue a Topology
Change Notification (TCN) BPDU to all other bridges. All bridges in the
LAN will re-calculate and determine who the root bridge is. The valid
value of Max. Age is 6 ~ 40 seconds. Default is 20 seconds.
