Huawei AR530 Series, Configuration Manual

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Dev
ice Comparison Configuration BPDU
After Comparison
Devi
ceB l
Port B1 receives the configuration BPDU {0,
0, 0, Port A1} from Port A1 and finds it superior
to its own configuration BPDU {0, 0, 0, Port
A1}, so Port B1 updates its configuration
BPDU.
l Port B2 receives the configuration BPDU {2,
0, 2, Port C2} from Port C2 and finds it inferior
to its own configuration BPDU {1, 0, 1, Port
B2}, so Port B2 discards the received
configuration BPDU.
l
Port B1: {0, 0, 0, Port
A1}
l Port B2: {1, 0, 1, Port
B2}
l DeviceB compares the configuration BPDU on
each port and finds that Port B1 has optimal
configuration BPDU. DeviceB selects Port B1
as the root port and retains the configuration
BPDU on Port B1.
l DeviceB calculates the configuration BPDU
{0, 5, 1, Port B2} for Port B2 based on the
configuration BPDU and path cost of the root
port, and compares the calculated
configuration BPDU with the original
configuration BPDU {1, 0, 1, Port B2} on Port
B2. The calculated configuration BPDU is
superior to the original one, so DeviceB selects
Port B2 as the designated port, replaces its
configuration BPDU with the calculated one,
and periodically sends the configuration BPDU
from Port B2.
l Root port (Port B1): {0,
0, 0, Port A1}
l Designated port (Port
B2): {0, 5, 1, Port B2}
Devi
ceC l Port C1 receives the configuration BPDU {0,
0, 0, Port A2} from Port A2 and finds it superior
to its own configuration BPDU {0, 0, 0, Port
A2}, so Port C1 updates its configuration
BPDU.
l Port C2 receives the configuration BPDU {1,
0, 1, Port B2} from Port B2 and finds it superior
to its own configuration BPDU {1, 0, 1, Port
B2}, so Port C2 updates its configuration
BPDU.
l Port C1: {0, 0, 0, Port
A2}
l
Port C2: {1, 0, 1, Port
B2}
Huawei AR530&AR550 Series Industrial Switch Routers
Configuration Guide - Ethernet Switching
6 STP/RSTP Configuration
Issue 01 (2014-11-30) Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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