Two Types of BPDUs To this point, the chapter has referred to all BPDUs as a single type. Actually, there are two types of BPDUs: Configuration BPDUs Topology Change Notification (TCN) BPDUs Configuration BPDUs are originated by the Root Bridge and flow outward along the active paths that radiate away from the Root Bridge. Topology Change Notification BPDUs flow … [Read more...]