Chapter 4: STP and RSTP

The following parameters refer to the designated root bridge. You cannot change these fields.

Designated Root - This parameter includes two fields: the root bridge priority and the MAC address of the root bridge. For example, 1000 00C08F1211BB shows the root bridge priority as 1000, and 00C08F1211BB as the MAC address.

Hello Time - This parameter is the Hello Me. See “Hello Time and Bridge Protocol Data Units (BPDU)” on page 68. This parameter affects only the root bridge.

Maximum Age - The parameter displays the maximum amount of time that BPDU’s are stored before being deleted on the root bridge.

Forward Delay - The parameter displays the time interval between generating and sending configuration messages by the root bridge.

The bottom section of the web page provides information about the bridge. The following parameters appear in the bottom third of the web page:

Bridge ID - The Bridge ID is the MAC address of the bridge. The bridge identifier is used as a tie breaker in the selection of the root bridge when two or more bridges have the same bridge priority.

You cannot change this parameter.

Bridge Priority - The priority number for the bridge, in hexadecimal format. This number is used to determine the root bridge for RSTP. The bridge with the lowest priority number is selected as the root bridge. If two or more bridges have the same priority value, that is, the lowest value of all the other bridges, then the bridge with the numerically lowest MAC address becomes the root bridge. When a root bridge goes offline, the bridge with the lowest priority number automatically takes over as the root bridge. This parameter can be from 0X0000 to 0XF000, with 0XF000 being the highest priority.

Bridge Hello Time - This is the time interval between generating and sending configuration messages by the bridge. This parameter is active only when the switch is the root bridge.

Bridge Maximum Age - The length of time after which stored bridge protocol data units (BPDU’s) are deleted by the bridge.

Bridge Forward Delay - This is the time interval between generating and sending configuration messages by the bridge.

5.Once you have configured the parameters, click Apply.

6.From the main menu on the left side of the page, select Save Configuration to Flash to permanently save your changes.

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Allied Telesis AT-S111, AT-GS950/48PS manual STP and Rstp