Dot1q termination VS vlan-type dot1q

Hello everyone,

Today I will share with you the differences between vlan-type dot1q and dot1q termination.

When the tagged packets are handled on the router, the VLAN termination interface is required.

Commonly, VLAN termination includes two types, dot1q and QinQ.

For dot1q interface, it handles the single VLAN tag packets, while the QinQ handles two VLAN tags packets.

The similarity betweenvlan-type dot1q and dot1q termination:

1. Both two commands are enabled under the sub-interface.

2. Both two commands are used to terminate the VLAN tag and send the packets with VLAN tag.

3. Both commands could bind VLANs to allow the different VLAN traffic.

4. The same sub-interfaces of the different main interfaces can be configured to terminate the same VLAN, while the different sub-interfaces of the same main interface cannot terminate the same VLAN.

Differences between vlan-type dot1q and dot1q termination:

1. The vlan-type dot1q can only bind one VLAN under a specific sub-interface, while dot1q termination could bind different VLANs on the same sub-interface with multi implements.

2. vlan-type dot1q could be executed directly under the sub-interface view, while the encapsulation dot1q-termination is required before the dot1q termination be implemented under the sub-interface view.

   

   Before the encapsulation dot1q-termination is configured, an error occurred when configuring command dot1q termination. 

   

   It's normal after the encapsulation dot1q-termination is added.

   

   No error occurred when implementing vlan-type dot1q directly.

3. For a dot1q termination sub-interface, the router wouldn’t send ARP packets by default, command arp broadcast enable is required to enable the ARP broadcast, while it’s unnecessary for vlan-type dot1q.

That is all I want to share with you!