HP 1910 User Manual page 207

Figure 179 STP network
As shown in Figure 179, the priority values of Device A, Device B, and Device C are 0, 1, and 2, and the
path costs of links among the three devices are 5, 10 and 4, respectively.
The spanning tree calculation process is as follows:
4. Device state initialization.
In Table 56, each configuration BPDU contains the following fields: root bridge ID, root path cost,
designated bridge ID, and designated port ID.
Table 56 Initial state of each device
Device
Device A
Device B
Device C
5. Configuration BPDUs comparison on each device.
In Table 57, each configuration BPDU contains the following fields: root bridge ID, root path cost,
designated bridge ID, and designated port ID.
Port name
AP1
AP2
BP1
BP2
CP1
CP2
194
BPDU of port
{0, 0, 0, AP1}
{0, 0, 0, AP2}
{1, 0, 1, BP1}
{1, 0, 1, BP2}
{2, 0, 2, CP1}
{2, 0, 2, CP2}