Providing redundancy in switched networks use Spanning Tree Protocol
STP is a network management protocol that is used to prevent loops in a redundant network topology. STP uses the Spanning Tree Algorithm (STA) to calculate the best switch path through the network. The Spanning Tree Protocol then shares this information with other switches on the network. Frames known as Bridge Protocol Data Units (BPDUs) are used to exchange STA calculations between switches. Using the information provided by the BPDUs, the Spanning Tree Protocol “prunes” redundant paths.