Introduction to Ethernet

Hello Daoud

First of all, these terms can be seen in the output of the show interface gigabitethernet 0/0 switchport command. Here is an example of that output:

SW1#show interfaces gigabitEthernet 0/0 switchport 
Name: Gi0/0
Switchport: Enabled
Administrative Mode: dynamic auto
Operational Mode: static access
Administrative Trunking Encapsulation: negotiate
Operational Trunking Encapsulation: native
Negotiation of Trunking: On
Access Mode VLAN: 1 (default)
Trunking Native Mode VLAN: 1 (default)
Administrative Native VLAN tagging: enabled
Voice VLAN: none
Administrative private-vlan host-association: none 
Administrative private-vlan mapping: none 
Administrative private-vlan trunk native VLAN: none
Administrative private-vlan trunk Native VLAN tagging: enabled
Administrative private-vlan trunk encapsulation: dot1q
Administrative private-vlan trunk normal VLANs: none
Administrative private-vlan trunk associations: none
Administrative private-vlan trunk mappings: none
Operational private-vlan: none
Trunking VLANs Enabled: ALL
Pruning VLANs Enabled: 2-1001
Capture Mode Disabled
Capture VLANs Allowed: ALL

Protected: false
Appliance trust: none
SW1#

The Administrative and Operational modes give us information about how the particular port is configured. Specifically:

  • Administrative Mode indicates what we actually configure on that particular port. For example, Trunk or Access or LaGP or PaGP or ON etc…
  • Operational Mode is the mode with which the port behaves in response to the configuration done onto a particular port, and its negotiation (if any) with the port on the other side of the link.

For example, if we connect two switches together and leave them in their default states, then the administrative mode would be dynamic auto, since by default, dynamic auto is enabled. That’s what they are configured with. But the operation mode will be static access, because the result of the negotiation is to have the ports be in access mode.

You can find out more information about this at the following lesson:

I hope this has been helpful!

Laz