Determine the Designated Port ( DP ) Spanning Tree Protocol

Switch 1 is the Root, Switch 2 is the DP, and Switch 3 is a non DP.
Switch 2 was elected as DP because of its lower BID value.
Finding the Designated Port
  1. The Switch with the lowest cost to the Root Bridge is elected as the Designated Port 
  2. If the cost is the same then the switch with the lowest BID is elected as the Designated Port