Rules For Creating The Tree Structure; Bridge Information; Setting Up The Tree Structure - Hirschmann RS20 User Manual

Spanning Tree
6.2 Rules for Creating the Tree
Structure
6.2.1

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).
6.2.2

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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6.2 Rules for Creating the Tree
UM RedundConfig L2P
Structure
Release 8.0 05/2013