User:Wikialpha

BPDUs - Switches send messages called Bridge Protocol Data Units (BPDUs) to allow the formation of a loop free logical topology.

Three types of BPDUs:

1. Configuration BPDU, used for Spanning Tree computation 2. Topology Change Notification (TCN) BPDU, used to announce changes in the network topology 3. Topology Change Notification Acknowledgment (TCA)

Reference BPDU Spanning tree protocol

Source image1 image2

Three types of BPDUs