>> The Root port is the one which is connected to the Root Bridge. As shown in the output of Switch 2 below, the Role of Ethernet 0/1 is “Root” which proves that this port connects to Switch1 (through Cross-over cable).

The designated port is the one which has the lower cost. The designated port is regarded as the forwarding port as compared to Non-Designated port which can be alternative to the designated port.

>> We can set a protection for each port of the switch such as we can set a specific mac-address which can access the port and if a device with some other MAC Address tries to connect to that port, the port can be turned-off or it can restrict the user.

>> The Switch with lowest priority is selected as a Root Bridge. If all the Switches have the same priority, then MAC Address serves as a tie for Root Bridge Election process. For small networks, the default settings work fine but if the network is larger, you can set the priority of the bridge yourself and set the priority of the Switch which occurs to be in the centre of the network lower. In this way, this switch will automatically become the root bridge and we will get an advantage that the STP will converge faster. The default time for the convergence of STP is 50 seconds. The priority can from 0 to 61440 where zero means the switch will always be the root bridge and 61440 means it can never be the root bridge. This value can be set in the increments of 4096.

>> The forward delay is the time it takes the switch port for the transition from Listening to Learning state. It can be seen in the Ethereal packets. The default value used in Switches is 15 Seconds as shown below:

To be continue …