CISCO SPANNING TREE PROTOCOL (STP)
Spanning Tree Protocol (STP) is a Layer 2 link control protocol, ensuring redundancy of the route while avoiding network loops. For a network Layer 2 to operate correctly, between any two stations only one active path should occur. It has three steps, which are Find the root bridge, Find the root port (R), Find the designated port (D).
Based on the Picture above, lets exercise and follow the command below,