STP(Spanning Tree Protocol) TYPES

STP(Spanning Tree Protocol) TYPES

SPANNING-TREE (Falling of trees)

COMMON SPANNING-TREE (802.1D)-

Also known as traditional spanning tree having one root bridge for all vlan. It consumes less CPU utilization.It has a forwarding delay of 15 to 30 seconds.

STATES-

BLOCKING,LISTENING,LEARNING,FORWARDING

PORT ROLES-

ROOT, DESIGNATED & BLOCKED

PER-VLAN SPANNING-TREE(Cisco Proprietary)-

This STP is based on per VLAN basis, Root-bridge for every VLAN. It is the default mode & consumes more CPU. PORT ROLES & STATES same as Common Spanning Tree.

RAPID SPANNING-TREE (802.1W)-

The forwarding delay is reduced to 3×2(Hello-interval) ie. 6 seconds.

 STATES-

DICARDING , LEARNING, FORWARDING (no BLOCKED & LISTENING)

 PORT ROLES-

ROOT, DESIGNATED, ALTERNATE & BACKUP

 MULTIPLE SPANNING-TREE (802.1s)-

 It has a group of VLANs under one instance of Root-bridge. Multiple VLANs are grouped as ONE VLAN. 15 instances can be created with each instance having upto 8 VLANS.