Siemens SCALANCE W1780 Configuration Manual page 271

● Root Cost
The path costs from this device to the root bridge.
● Topology Changes / Last Topology Change
The entry for the device shows the number of reconfiguration actions due to the spanning
tree mechanism since the last startup. For the root bridge, the time since the last
reconfiguration is displayed as follows:
– Seconds: "sec" unit after the number
– Minutes: "min" unit after the number
– Hour: "hr" unit after the number
● Topology Changes / Last Topology Change
Each bridge regularly sends configuration frames (BPDUs). The interval between two such
frames is the Hello time. The default for this parameter is 2 seconds.
● Bridge Forward Delay[s] / Root Forward Delay[s]
New configuration data is not used immediately by a bridge but only after the period
specified in the forward delay parameter. This ensures that operation is started with the new
topology only after all the bridges have the required information. The default for this
parameter is 15 seconds.
● Bridge Max Age / Root Max Age
valid by the switch. The default for this parameter is 20 seconds.
● Bridge Max Hop Count
This parameter specifies how many MSTP nodes a BPDU may pass through. If an MSTP
BPDU is received and has a hop count that exceeds the value configured here, it is
discarded. The default for this parameter is 20.
● Regional root priority
For a description of the displayed values, see Bridge priority / Root priority
● Regional root address
Shows the MAC address of the regional root bridge.
● Regional Root Cost
Shows the path costs from this device to the regional root bridge.
● Region Name
Enter the name of the MSTP region to which this device belongs. As default, the MAC
address of the device is entered here. This value must be the same on all devices that
belong to the same MSTP region.
● Region Version
Enter the version number of the MSTP region in which the device is located. This value must
be the same on all devices that belong to the same MSTP region.
● Reset Counters
Click this button to reset the counters on this page.
SCALANCE W1780/W1740 according to IEEE 802.11ac Web Based Management
Configuration Manual, 11/2019, C79000-G8976-C485-03
Bridge Max Age defines the maximum "age" of a received BPDU for it to be accepted as
Configuring with Web Based Management
6.7 "Layer 2" menu
271