Siemens SIMATIC NET SCALANCE W780 Series Configuration Manual page 133

Description
The page contains the following boxes:
● Spanning Tree Mode
Shows the set mode. You specify the mode in "Layer 2 > Configuration" and in "Layer 2 >
MSTP > General".
The following values are possible:
– '-'
– STP
– RSTP
– MSTP
● Instance ID
Shows the number of the instance. The parameter depends on the configured mode.
● Bridge Priority / Root Priority
Which device becomes the root bridge is decided based on the bridge priority. The bridge
with the highest priority (in other words, with the lowest value for this parameter) becomes
the root bridge. If several devices in a network have the same priority, the device whose
MAC address has the lowest numeric value will become the root bridge. Both
parameters, bridge priority and MAC address together form the bridge identifier. Since
the root bridge manages all path changes, it should be located as centrally as possible
due to the delay of the frames. The value for the bridge priority is a whole multiple of
4096 with a range of values from 0 to 32768.
● Bridge Address / Root Address
The bridge address shows the MAC address of the device and the root address shows
the MAC address of the root bridge.
● Root Cost
The path costs from this device to the root bridge.
● Bridge Status
Shows the status of the bridge, e.g. whether or not the device is the root bridge.
● Regional root priority (available only with MSTP)
For a description, see Bridge priority / Root priority
● Regional root address (available only with MSTP)
Shows the MAC address of the regional root bridge.
● Regional Root Cost (available only with MSTP)
Shows the path costs from this device to the regional root bridge.
SCALANCE W780/W740 to IEEE 802.11n Web Based Management
Configuration Manual, 08/2018, C79000-G8976-C267-13
Configuring with Web Based Management
6.4 "Information" menu
133