9E312/9E423 Module Bridging

A lower assigned value gives the port a higher Priority when BPDUs are compared. The allowable range is 0-FF hexadecimal (0-255 decimal); the default is 80 hexadecimal.

Path Cost

Displays the cost that this port will contribute to the calculation of the overall Root path cost in a Configuration BPDU transmitted by this bridge port. You can lower a port’s Path Cost to make the port more competitive in the selection of the Designated Port — for example, you may want to assign a lower path cost to a port on a higher performance bridge. The allowable range is 1 to 65535.

Designated Cost

Displays the cost of the path to the Root Bridge of the Designated Port on the LAN to which this port is attached. This cost is added to the Path Cost to test the value of the Root Path Cost parameter received in Configuration BPDUs.

Designated Root

Displays the unique bridge identifier of the bridge that is assumed to be the Root Bridge.

Designated Bridge

Displays the network address portion of the Bridge ID (MAC address/priority component) for the bridge that is believed to be the Designated Bridge for the LAN associated with this port.

The Designated Bridge ID, along with the Designated Port and Port Identifier parameters for the port, is used to determine whether this port should be the Designated Port for the LAN to which it is attached. The Designated Bridge ID is also used to test the value of the Bridge Identifier parameter in received BPDUs.

Designated Port

Displays the network address portion of the Port ID (which includes a manageable priority component) of the port believed to be the Designated Port for the LAN associated with this port.

The Designated Port ID, along with the Designated Bridge and Port Identifier parameters for the port, is used to determine whether this port should be the Designated Port for the LAN to which it is attached. Management also uses it to determine the Bridged LAN topology.

Topology

This indicates how many times the bridge’s Topology Change flag has been changed since the 9E312/9E423 Module was last powered-up or initialized. It also indicates the date and time at which the topology was last changed. The Topology Change flag increments each time a bridge enters or leaves the network, or when the Root Bridge ID changes.

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Bridge Spanning Tree

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Cabletron Systems 9E312, 9E423 Path Cost, Designated Cost, Designated Root, Designated Bridge, Designated Port, Topology