ZyXEL ES-2108PWR User Guide - Page 108

Chapter 11 Spanning Tree Protocol Table 25 Advanced Application > Spanning Tree Protocol > RSTP (continued) LABEL DESCRIPTION Max Age This is the maximum time (in seconds) a switch can wait without receiving a BPDU before attempting to reconfigure. All switch ports (except for designated ports) should receive BPDUs at regular intervals. Any port that ages out STP information (provided in the last BPDU) becomes the designated port for the attached LAN. If it is a root port, a new root port is selected from among the switch ports attached to the network. The allowed range is 6 to 40 seconds. Forwarding Delay This is the maximum time (in seconds) a switch will wait before changing states. This delay is required because every switch must receive information about topology changes before it starts to forward frames. In addition, each port needs time to listen for conflicting information that would make it return to a blocking state; otherwise, temporary data loops might result. The allowed range is 4 to 30 seconds. As a general rule: Note: 2 * (Forward Delay - 1) >= Max Age >= 2 * (Hello Time + 1) Port This field displays the port number. * Settings in this row apply to all ports. Use this row only if you want to make some settings the same for all ports. Use this row first to set the common settings and then make adjustments on a port-by-port basis. Active Priority Path Cost Apply Cancel Note: Changes in this row are copied to all the ports as soon as you make them. Select this check box to activate STP on this port. Configure the priority for each port here. Priority decides which port should be disabled when more than one port forms a loop in a switch. Ports with a higher priority numeric value are disabled first. The allowed range is between 0 and 255 and the default value is 128. Path cost is the cost of transmitting a frame on to a LAN through that port. It is assigned according to the speed of the bridge. The slower the media, the higher the cost - see Table 22 on page 102 for more information. Click Apply to save your changes to the Switch's run-time memory. The Switch loses these changes if it is turned off or loses power, so use the Save link on the top navigation panel to save your changes to the non-volatile memory when you are done configuring. Click Cancel to reset the fields. 11.5 Rapid Spanning Tree Protocol Status Click Advanced Application > Spanning Tree Protocol in the navigation panel to display the status screen as shown next. See Section 11.1 on page 101 for more information on RSTP. " This screen is only available after you activate RSTP on the Switch. 108 ES-2108 Series User's Guide