BPDU
In
STP (Spanning Tree Protocol), a BPDU is a packet that initiates communication between devices. BPDU
packets contain information on ports, addresses, priorities, and costs and they ensure that
the data ends up where it was intended to go. BPDU messages are exchanged across bridges to
detect loops in a network topology. The loops are then removed by shutting down selected
bridge interfaces and placing redundant switch ports in a backup, or blocked,
state.