Spanning Tree Protocol, also known as STP, was produced to provide a methodology for bridges to achieve Layer 2 routing with redundant, loop-free operation. Spanning Tree Protocol is defined as a protocol in which two bridges interconnect two computer network segments and allow the bridges to exchange information. In this way, only one of the bridges will be responsible for processing a message sent between the two computers within this same network. Removing STP and connecting the switches in a loop will cause the broadcast packet to be duplicated because there is nothing at Layer 2 that can prevent a loop. STP exchanges BPDU messages with other switches to detect loops. BPDU is just one of the necessary components that STP uses to do its job. STP also uses other components which include, but are not limited to, root port, block port, and designated port. Say no to plagiarism. Get a tailor-made essay on “Why violent video games should not be banned”?Get the original essayBridge Protocol Data Unit (BPDU) is a data message exchanged between switches transmitted in frames over a local network. BDPU is used to detect loops in network topologies. BPDU frames contain information about switch IDs, addresses, MAC address, originating switch ports, and switch port priority. The information contained in BPDU is necessary to configure an STP topology as well as to maintain it. BPDU notifies other switches of port changes. BPDU is actively used in STP when using the Spanning Tree Algorithm (STA). What happens is that when BPDUs are received, the switch uses a mathematical formula, the Spanning Tree algorithm. This is used to know when there is a Layer 2 switching loop in the network. This later determines which of the ports will eventually need to be closed and shut down. There are actually three types of BPDUs. These are Configuration BPDU (CBPDU), Topology Change Notification (TCN), and Topology Change Notification Acknowledgment (TCA). The CBPDU is a packet sent between bridges in a network to configure device interfaces. This is done either in a transfer state or in a blocking state. The TCN is used by the bridge when it needs to signal a topology change. The TCN is sent to the root port of the bridge. TCA is used to acknowledge receipt of a configuration message. The main use and goal of implementing Bridge Protocol data units with the Spanning Tree algorithm is to avoid Layer 2 switching loops and also so-called broadcast storms. By using the BPDU units, this objective can be achieved. A bridge contains two or possibly more ports. The two ports that are often confused and conveniently located on the bridge are the root and designated ports. The port connected to the same side as the STP root can be located is the root port. The root port is the port on the bridge, or switch, that has the lowest spanning tree path cost, extending from the root bridge to the switch. There is and can only be one root port on a bridge. When a bridge has multiple paths to choose from to reach the root bridge, the bridge chooses one path, usually the shortest, to be designated as the root port. A root port can also be identified as a port that is oriented "upstream" and always faces or points toward the root bridge. A designated port is the port on a local area network (LAN) segment that has the least path. cost.