Alcatel Carrier Internetworking Solutions 8008 manual

STA (Spanning Tree Algorithm)

When the Switch Becomes Root

Parameter	Default	Description
Hello Time	2	The time interval (in seconds) at which the root device
		transmits a configuration message.
		The minimum value is 1.
		The maximum value is the lower of
		10 or [(Max. Message Age / 2) -1].
Max (Message) Age	20	The maximum time (in seconds) a device can wait
		without receiving a configuration message before
		attempting to reconfigure. All device ports (except for
		designated ports) should receive configuration
		messages at regular intervals. Any port that ages out
		STA information (provided in the last configuration
		message) becomes the designated port for the attached
		LAN. If it is a root port, a new root port is selected from
		among the device ports attached to the network.
		The minimum value is the higher of
		6 or [2 x (Hello Time + 1)].
		The maximum value is the lower of
		40 or [2 x (Forward Delay - 1)].
Forward Delay	15	The maximum time (in seconds) the root device will wait
		before changing states (i.e., listening to learning to
		forwarding). This delay is required because every

device must receive information about topology changes before it starts to forward frames. In addition, each port needs time to listen for conflicting information that would make it return to a blocking state; otherwise, temporary data loops might result.

Maximum value is 30.

Minimum value is the higher of 4 or [(Max. Message Age / 2) + 1].

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