HP A6600 Configuration Manual page 53

Device Comparison process
•
Port B1 receives the configuration BPDU of Port A1
{0, 0, 0, Port A1}, finds that the received
configuration BPDU is superior to its existing
configuration BPDU {1, 0, 1, Port B1}, and updates its
configuration BPDU.
•
Port B2 receives the configuration BPDU of Port C2
{2, 0, 2, Port C2}, finds that its existing configuration
BPDU {1, 0, 1, Port B2} is superior to the received
configuration BPDU, and discards the received one.
•
Device B compares the configuration BPDUs of all its
ports, decides that the configuration BPDU of Port B1
Device B
is the optimum, and selects Port B1 as the root port
with the configuration BPDU unchanged.
•
Based on the configuration BPDU and path cost of the
root port, Device B calculates a designated port
configuration BPDU for Port B2 {0, 5, 1, Port B2}, and
compares it with the existing configuration BPDU of
Port B2 {1, 0, 1, Port B2}. Device B finds that the
calculated one is superior, decides that Port B2 is the
designated port, replaces the configuration BPDU on
Port B2 with the calculated one, and periodically
sends out the calculated configuration BPDU.
•
Port C1 receives the configuration BPDU of Port A2
{0, 0, 0, Port A2}, finds that the received
configuration BPDU is superior to its existing
configuration BPDU {2, 0, 2, Port C1}, and updates
its configuration BPDU.
•
Port C2 receives the original configuration BPDU of
Port B2 {1, 0, 1, Port B2}, finds that the received
configuration BPDU is superior to the existing
configuration BPDU {2, 0, 2, Port C2}, and updates
its configuration BPDU.
•
Device C compares the configuration BPDUs of all its
Device C
ports, decides that the configuration BPDU of Port C1
is the optimum, and selects Port C1 as the root port
with the configuration BPDU unchanged.
•
Based on the configuration BPDU and path cost of the
root port, Device C calculates the configuration BPDU
of Port C2 {0, 10, 2, Port C2}, and compares it with
the existing configuration BPDU of Port C2 {1, 0, 1,
Port B2}. Device C finds that the calculated
configuration BPDU is superior to the existing one,
selects Port C2 as the designated port, and replaces
the configuration BPDU of Port C2 with the calculated
one.
46
Configuration BPDU on
ports after comparison
•
Port B1: {0, 0, 0, Port
A1}
•
Port B2: {1, 0, 1, Port
B2}
•
Root port (Port B1): {0,
0, 0, Port A1}
•
Designated port (Port
B2): {0, 5, 1, Port B2}
•
Port C1: {0, 0, 0, Port
A2}
•
Port C2: {1, 0, 1, Port
B2}
•
Root port (Port C1): {0,
0, 0, Port A2}
•
Designated port (Port
C2): {0, 10, 2, Port
C2}