H3C Technologies H3C S3100 Series Switches - Manual (Page 204)

Operation Manual – MSTP
H3C S3100-52P Ethernet Switch
Chapter 1 MSTP Configuration
1-29
Transmissio
n speed
Operation
mode
(half-/full-dup
lex)
802.1D-1998 IEEE 802.1t
Proprietary
standard
100 Mbps
Half-duplex/F
ull-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, the path cost of a port operating in full-duplex mode is slightly less than that of
the port operating in half-duplex mode.
When calculating the path cost of an aggregated link, 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 transmission speed.
In this formula, the link transmission speed is the sum of the speeds of all the unblocked
ports on the aggregated link, which is measured in 100 Kbps.