LevelOne GSW-1676, User Manual

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RSTP
6-53
during reconfiguration events, does not cause the spanning tree to
initiate reconfiguration when the interface changes state, and also
overcomes other STA-related timeout problems. However, remember
that Edge Port should only be enabled for ports connected to an
end-node device. (Default: Enabled)
• Path Cost - This parameter is used by the STA to determine the best
path between devices. Therefore, lower values should be assigned to
ports attached to faster media, and higher values assigned to ports with
slower media. (Path cost takes precedence over port priority.)
(Range: 0 for auto-configuration, 1-65535 for the short path cost
method, 1-200,000,000 for the long path cost method)
By default, the system automatically detects the speed and duplex mode
used on each port, and configures the path cost according to the values
shown below. Path cost “0” is used to indicate auto-configuration mode.
Note that when Force Version is set to Compatible mode (STP) and the
default path cost recommended by the IEEE 8021w standard exceeds
65,535, the default is set to 65,535.
Recommended STA Path Cost Range
Port Type
IEEE 802.1D-1998 IEEE 802.1w-2001
Ethernet 50-600 200,000-20,000,000
Fast Ethernet 10-60 20,000-2,000,000
Gigabit
Ethernet
3-10 2,000-200,000
Default STA Path Costs
Port Type
Link Type IEEE 802.1w-2001
Ethernet Half Duplex
Full Duplex
Trunk
2,000,000
1,000,000
500,000
Fast Ethernet Half Duplex
Full Duplex
Trunk
200,000
100,000
50,000
Gigabit
Ethernet
Full Duplex
Trunk
10,000
5,000