PVST+: Per-VLAN Spanning Tree Explained
Classic STP runs one spanning tree for the entire switched network, no matter how many VLANs exist. That means every VLAN shares the same root bridge and the same blocked links — one uplink ends up carrying nothing while every other uplink carries everything, regardless of which VLANs actually need which paths. PVST+ (Per-VLAN Spanning...
