2
In this Scenario we leave the Port Priority at it’s default Value
The lowest SENDER Port ID is used to Break the Tie
Switch S4 is our Subject Switch it is receiving BPDU’s from Switch S1, thus S1 is the Sender
Since Port F0/1 has a lower number than Port F0/2 on Switch S1
Port F0/6 will become the Root Port and Port F0/5 will become the Alternate Port on Switch S4