202 Configuring WSS System ParametersNN47250-102 (320666-G Version 02.01)• If STP is disabled on the VLAN, spanning tree packets are forwarded transparently throughthe VLAN to and from that port.6 In the Port Priority box, specify a priority value (0 to 255). The default is 128.7 In the Path Cost box, specify a value (0 to 65,535) for the cost. The default depends on the port speed andlink type:• 1000 Mbps, full duplex aggregate link (port group)—19• 1000 Mbps, full duplex—4• 100 Mbps, full duplex aggregate link (port group)—19• 100 Mbps, full duplex—18• 100 Mbps, half duplex—19• 10 Mbps, full duplex aggregate link (port group)—19• 10 Mbps, full duplex—95• 10 Mbps, half duplex—100Specify 0 to use the default cost for the port based on link speed.8 To enable port fast convergence, select the PortFast checkbox.Port fast convergence bypasses both the listening and learning stages and immediately places a port in theforwarding state. Use port fast convergence on network ports that are directly connected to servers, hosts,or other MAC stations.9 Click OK.Enabling STP Fast Convergence FeaturesThe standard STP timers delay traffic forwarding briefly after a topology change. The time a port takes to change fromthe listening state to the learning state or from the learning state to the forwarding state is called the forwarding delay. Insome configurations, this delay is unnecessary.The WSS provides the following fast convergence features to bypass the forwarding delay:• Backbone fast convergence—Backbone fast convergence accelerates a port’s recovery following the failure of anindirect link. Normally, when a forwarding link fails, a bridge that is not directly connected to the link does notdetect the link change until the maximum age timer expires. Backbone fast convergence enables the WSS to listenfor bridge protocol data units (BPDUs) sent by a designated bridge when the designated bridge’s link to the rootbridge fails, and immediately verifies whether BPDU information stored on a port is still valid. If the BPDUinformation on the port is no longer valid, the bridge immediately starts the listening stage on the port.Note. Do not use port fast convergence on ports connected to other bridges.Note. If you plan to use the backbone fast convergence feature, you mustenable it on all the bridges in the spanning tree.
