Spanning Tree Algorithm Configuration 3

•Designated Port – The port priority and number of the port on the designated bridging device through which this switch must communicate with the root of the Spanning Tree.

•Oper Path Cost – The contribution of this port to the path cost of paths towards the spanning tree root which include this port.

•Oper Link Type – The operational point-to-point status of the LAN segment attached to this interface. This parameter is determined by manual configuration or by auto-detection, as described for Admin Link Type in STA Port Configuration on page 3-123.

•Oper Edge Port – This parameter is initialized to the setting for Admin Edge Port in STA Port Configuration on page 3-123(i.e., true or false), but will be set to false if a BPDU is received, indicating that another bridge is attached to this port.

•Port Role – Roles are assigned according to whether the port is part of the active topology connecting the bridge to the root bridge (i.e., root port), connecting a LAN through the bridge to the root bridge (i.e., designated port), or is the MSTI regional root (i.e., master port); or is an alternate or backup port that may provide connectivity if other bridges, bridge ports, or LANs fail or are removed. The role is set to disabled (i.e., disabled port) if a port has no role within the spanning tree.

Alternate port receives more useful BPDUs from another bridge and is therefore not selected as the designated

port.R
R: Root PortA:Alternate PortD:Designated PortB:Backup Port

R

AD B

x

Backup port receives more useful BPDUs from the same bridge and is therefore not selected as the designated

port.

RR

ADB

x

•Trunk Member – Indicates if a port is a member of a trunk. (STA Port Information only)

3-121