Command Manual (For Soliton) – MSTP
H3C S3100 Series Ethernet Switches
Chapter 1 MSTP Configuration Commands
1-44
Table 1-8
Link speeds and the corresponding path costs
Link speed
Operating mode
(half-/full-duplex)
802.1D-
1998
IEEE 802.1t
Proprietary
standard
0 —
65,535
200,000,000
200,000
10 Mbps
Half-duplex/Full-duplex
Aggregated link 2 ports
Aggregated link 3 ports
Aggregated link 4 ports
100
95
95
95
200,000
1,000,000
666,666
500,000
2,000
1,800
1,600
1,400
100 Mbps
Half-duplex/Full-duplex
Aggregated link 2 ports
Aggregated link 3 ports
Aggregated link 4 ports
19
15
15
15
200,000
100,000
66,666
50,000
200
180
160
140
1,000 Mbps
Full-duplex
Aggregated link 2 ports
Aggregated link 3 ports
Aggregated link 4 ports
4
3
3
3
200,000
10,000
6,666
5,000
20
18
16
14
10 Gbps
Full-duplex
Aggregated link 2 ports
Aggregated link 3 ports
Aggregated link 4 ports
2
1
1
1
200,000
1,000
666
500
2
1
1
1
Normally, when a port operates in full-duplex mode, the corresponding path cost is
slightly less than that when the port operates in half-duplex mode.
When the path cost of an aggregated link is calculated, the 802.1D-1998 standard does
not take the number of the ports on the aggregated link into account, whereas the
802.1T standard does. The following formula is used to calculate the path cost of an
aggregated link:
Path cost = 200,000 / link speed,
In this formula, the link speed is the sum of the speeds of the unblocked ports on the
aggregated link, which is measured in 100 Kbps.
Examples
# Configure to use the IEEE 802.1D-1998 standard to calculate the default path costs
of ports.
<Sysname> system-view
System View: return to User View with Ctrl+Z.
[Sysname] stp pathcost-standard dot1d-1998
# Configure to use the IEEE 802.1t standard to calculate the default path costs of ports.
<Sysname> system-view