HP V1910 manual BP2 with the configuration Bpdu of BP2. If the calculated, CP2 1, 0, 1, BP2

Device	Comparison process		Configuration BPDU on
			ports after comparison
	∙ Port BP1 receives the configuration BPDU of Device A {0, 0, 0,
		AP1}. Device B finds that the received configuration BPDU is
		superior to the configuration BPDU of the local port {1, 0, 1,
		BP1}, and updates the configuration BPDU of BP1.	BP1: {0, 0, 0, AP1}
	∙	Port BP2 receives the configuration BPDU of Device C {2, 0, 2,
			BP2: {1, 0, 1, BP2}
		CP2}. Device B finds that the configuration BPDU of the local
		port {1, 0, 1, BP2} is superior to the received configuration
		BPDU, and therefore discards the received configuration
		BPDU.
	∙ Device B compares the configuration BPDUs of all its ports, and
Device B		determines that the configuration BPDU of BP1 is the optimum
		configuration BPDU. Then, it uses BP1 as the root port, the
		configuration BPDUs of which will not be changed.
	∙	Based on the configuration BPDU of BP1 and the path cost of	Root port BP1:
		the root port (5), Device B calculates a designated port	{0, 0, 0, AP1}
		configuration BPDU for BP2 {0, 5, 1, BP2}.
			Designated port BP2:
	∙	Device B compares the calculated configuration BPDU {0, 5, 1,
			{0, 5, 1, BP2}
		BP2} with the configuration BPDU of BP2. If the calculated
		BPDU is superior, BP2 will act as the designated port, and the
		configuration BPDU on this port will be replaced with the
		calculated configuration BPDU, which will be sent out
		periodically.
	∙ Port CP1 receives the configuration BPDU of Device A {0, 0, 0,
		AP2}. Device C finds that the received configuration BPDU is
		superior to the configuration BPDU of the local port {2, 0, 2,
		CP1}, and updates the configuration BPDU of CP1.	CP1: {0, 0, 0, AP2}
	∙	Port CP2 receives the configuration BPDU of port BP2 of Device
			CP2: {1, 0, 1, BP2}
		B {1, 0, 1, BP2} before the configuration BPDU is updated.
		Device C finds that the received configuration BPDU is superior
		to the configuration BPDU of the local port {2, 0, 2, CP2}, and
		therefore updates the configuration BPDU of CP2.
	After comparison:
	∙ The configuration BPDU of CP1 is elected as the optimum
		configuration BPDU, so CP1 is identified as the root port, the	Root port CP1:
Device C		configuration BPDUs of which will not be changed.	{0, 0, 0, AP2}
	∙ Device C compares the calculated designated port
			Designated port CP2:
		configuration BPDU {0, 10, 2, CP2} with the configuration
			{0, 10, 2, CP2}
		BPDU of CP2, and CP2 becomes the designated port, and the

configuration BPDU of this port will be replaced with the calculated configuration BPDU.

∙Then, port CP2 receives the updated configuration BPDU of

	Device B {0, 5, 1, BP2}. Because the received configuration
	BPDU is superior to its own configuration BPDU, Device C	CP1: {0, 0, 0, AP2}
	launches a BPDU update process.
		CP2: {0, 5, 1, BP2}
∙	At the same time, port CP1 receives periodic configuration
	BPDUs from Device A. Device C does not launch an update
	process after comparison.

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