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H3C Technologies H3C WX5500E Series Access Controllers User Manual

Page 90

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79

Specifying a standard for the device to use when it calculates
the default path cost

CAUTION:

If you change the standard that the device uses to calculate the default path costs, you restore the path
costs to the default.

You can specify a standard for the device to use in automatic calculation of the default path cost. The
device supports the following standards:

dot1d-1998—The device calculates default path costs for ports based on IEEE 802.1d-1998.

dot1t—The device calculates default path costs for ports based on IEEE 802.1t.

legacy—The device calculates default path costs for ports based on a private standard.

Table 13

shows a comparison between link speeds and path costs for each of these standards.

Table 13 Mappings between the link speed and the path cost

Link speed

Port type

Path cost
IEEE

802.1d-1998

IEEE 802.1t

Private standard

0 N/A

65535

200,000,000

200,000

10 Mbps

Single port

100

2,000,000 2000

Aggregate interface
containing 2 Selected ports

1,000,000 1800

Aggregate interface
containing 3 Selected ports

666,666 1600

Aggregate interface
containing 4 Selected ports

500,000 1400

100 Mbps

Single port

19

200,000 200

Aggregate interface
containing 2 Selected ports

100,000 180

Aggregate interface
containing 3 Selected ports

66,666 160

Aggregate interface
containing 4 Selected ports

50,000 140

1000 Mbps

Single port

4

20,000 20

Aggregate interface
containing 2 Selected ports

10,000 18

Aggregate interface
containing 3 Selected ports

6666 16

Aggregate interface
containing 4 Selected ports

5000 14