
Relationship with Other Parameters
You can change the parameter value by setting the port priority. In this case, however, the
topology of the spanning tree may be rearranged.
If the port priority is smaller, the port ID is smaller. When the port priorities are the same, the
port ID is smaller if the port number is smaller.
7.78 Designated Path Cost
Description
The
Designated Path Cost
parameter is applicable to the port and is used for the state machine
calculation of the spanning tree. Based on the port path cost, you can calculate the root path cost
of the port of the switch. The root path cost is equal to 0 in the case of a root bridge. In the case
of other bridges, the root path cost of the bridge refers to the path cost from the root bridge to
this bridge. The root path cost is the sum of the minimum root path cost of the port on this bridge
and the path cost of this port. The path cost of each port can be set through the management
module.
shows the recommended values of the port path cost. The values are generally
related to the MAC type and transmission rate.
Table 7-9
Recommended values of the port path cost
Parameter
Link Speed
Recommende
d value
Recommende
d range
Range
Path Cost
<=100 Kb/s
200000000
20000000-2000
00000
1-200000000
1 Mb/s
20000000
2000000-20000
0000
1-200000000
10 Mb/s
2000000
200000-200000
00
1-200000000
100 Mb/s
200000
20000-2000000
1-200000000
1 Gb/s
20000
2000-200000
1-200000000
10 Gb/s
2000
200-20000
1-200000000
100 Gb/s
200
20-2000
1-200000000
1 Tb/s
20
2-200
1-200000000
10 Tb/s
2
1-20
1-200000000
Impact on the System
This parameter affects the calculation of the root path cost based on the STP and hence affects
the service flow in the spanning tree.
OptiX OSN 550 Multi-Service CPE Optical Transmission
System
Configuration Guide
7 List of Parameters
Issue 02 (2011-06-30)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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