Example: Manipulation Of A Tree Structure - Hirschmann PowerMICE User Manual

Rapid Spanning Tree

1.1.6 Example: manipulation of a tree structure

The management administrator of the network soon discovers that this con-
figuration, with bridge 1 as its root bridge (see
root paths" on page
sends to the other bridges are concentrated on the paths between bridge 1
and bridge 2 and between bridge 1 and bridge 3.
If the management administrator raises bridge 2 to the root bridge, the load
caused by the control packets will be more evenly distributed among the sub-
networks. This would result in the configuration shown
between the individual bridges and the root bridge have become shorter.
P-BID = 40 960
Bridge 7
Priority of the bridge identifikation (BID)
P-BID
= BID without MAC Address
Root path
Interrupted path
Fig. 7: Example of a tree structure manipulation
24
20) , is unfavorable. The control packets that bridge 1
P-BID = 16 384
Bridge 2
P-BID = 20 480
Port 2
Bridge 4
Port 1
P-BID = 36 864
Port 3
Bridge 6
1.1 The Spanning Tree Protocol
"Example: determination of
(see Fig.
P-BID = 24 576 P-BID = 32 768
Bridge 3 Bridge 1
P-BID = 28 672
Bridge 5
7). The paths
Redundancy L3P
Release 3.0 01/07