Spanning Tree
5.2 Rules for Creating the Tree
Structure
5.2.1
Bridge information
To determine the tree structure, the bridges need more detailed information
about the other bridges located in the network.
To obtain this information, each bridge sends a BPDU (Bridge Protocol Data
Unit) to the other bridges.
The contents of a BPDU include
bridge identifier,
root path costs and
port identifier
(see IEEE 802.1D).
5.2.2
Setting up the tree structure
The bridge with the smallest number for the bridge identifier is called the
root bridge. It is (or will become) the root of the tree structure.
The structure of the tree depends on the root path costs. Spanning Tree
selects the structure so that the path costs between each individual bridge
and the root bridge become as small as possible.
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5.2 Rules for Creating the Tree
UM Redundancy Configuration L2E
Structure
Release 7.1 12/2011