METRODATA LTD
WCM1100 / WCM3100 / WCM-Serial
User Manual
76-02-082 Rev J
69 of 140
5.3.1.9.3 RSTP
When RSTP is enabled on the WCM unit, there are several parameters which need to be
defined on a per port basis. The port rstp menu is shown below:
Metrodata WCM3100 "" Alarms: Major
RSTP, LAN1
Priority 128
Cost 0
portFast Disabled
First CAPITAL - select item
<escape> - exit menu
5.3.1.9.3.1 RSTP Port Priority
The port priority is used by the RSTP algorithm to determine which connections should be
used.
5.3.1.9.3.2 RSTP Port Cost
The port cost is used by the RSTP algorithm to determine which connections should be
used.
5.3.1.9.3.3 RSTP Port Fast
When RSTP is enabled, a port will power up in the blocked state and listen for BPDU
’s in
order to determine the network topology, and whether it should transition to the forwarding
state. In the event that a port running RSTP is connected to a port which is not, then
eventually after a timeout when no BPDU
’s are received the port will decide that it may
transition to the forwarding state.
By enabling Port Fast on a port, the user is declaring that it is not possible for the this port
to form a loop, and it should therefore transition to forwarding immediately.
