Configuring A Port As An Edge Port; Configuring The Path Cost For A Port - 3Com 4500 PWR 26-Port Configuration Manual

Configuring the Timeout Time Factor
Refer to Configuring the Timeout Time
Configuring the Maximum Transmitting Rate on the Current Port
Refer to Configuring the Maximum Transmitting Rate on the Current

Configuring a Port as an Edge Port

Refer to Configuring the Current Port as an Edge

Configuring the Path Cost for a Port

The path cost parameter reflects the rate of the link connected to the port. For a port on an
MSTP-enabled switch, the path cost may be different in different MSTIs. You can enable flows of
different VLANs to travel along different physical links by configuring appropriate path costs on ports, so
that VLAN-based load balancing can be implemented.
Path cost of a port can be determined by the switch or through manual configuration.
Standards for calculating path costs of ports
Currently, a switch can calculate the path costs of ports based on one of the following standards:
dot1d-1998: Adopts the IEEE 802.1D-1998 standard to calculate the default path costs of ports.
dot1t: Adopts the IEEE 802.1t standard to calculate the default path costs of ports.
legacy: Adopts the proprietary standard to calculate the default path costs of ports.
Follow these steps to specify the standard for calculating path costs:
To do...
Enter system view
Specify the standard for
calculating the default path
costs of the links connected to
the ports of the switch
Table 20-7 Transmission rates vs. path costs
Rate
0
10 Mbps
100 Mbps
Factor.
system-view
stp pathcost-standard
{ dot1d-1998 | dot1t | legacy }
Operation mode
(half-/full-duplex)
—
Half-duplex/Full-duplex
Aggregated link 2 ports
Aggregated link 3 ports
Aggregated link 4 ports
Half-duplex/Full-duplex
Aggregated link 2 ports
Aggregated link 3 ports
Aggregated link 4 ports
Port.
Use the command...
802.1D-1998
65,535
100
95
95
95
19
15
15
15
20-30
Port.
Remarks
—
Optional
By default, the legacy standard
is used to calculate the default
path costs of ports.
Latency
IEEE 802.1t
standard
200,000,000 200,000
2,000,000 2,000
1,000,000 1,800
666,666 1,600
500,000 1,400
200,000 200
100,000 180
66,666 160
50,000 140