Example Of Tree Structure Manipulation - Hirschmann RS20 User Manual

Spanning Tree
4.5 Example of Tree Structure
Manipulation
The Management Administrator soon discovers that this configuration with
bridge 1 as the root bridge (see on page 10 „Example of Root Path
Determination") is unfavorable. On the paths from bridge 1 to bridge 2 and
bridge 1 to bridge 3, the control packets which the root bridge sends to all
other bridges are adding up.If the Management Administrator makes bridge
2 the root bridge, the burden of the control packets on the subnetworks is
distributed much more evenly. The result is the configuration shown here
(see fig. 20). The distances between the individual bridges and the root
bridge are now shorter.
P-BID = 40 960 P-BID = 20 480
Bridge 7 Bridge 4
Priority of the bridge identifikation (BID)
P-BID
= BID without MAC Address
Root path
Interrupted path
Figure 20: Example of tree structure manipulation
52
P-BID = 16 384
Bridge 2
Port 2
Port 1
P-BID = 36 864
Port 3
Bridge 6
4.5 Example of Tree Structure Mani-
P-BID = 24 576 P-BID = 32 768
Bridge 3 Bridge 1
P-BID = 28 672
Bridge 5
pulation
Redundancy
Release 6.0 07/2010