If The Vlan Tag Is Present In An Ethernet Frame, What Is The Maximum Frame Size?

If the VLAN tag is present in an ethernet frame, what is the maximum frame size?
The maximum size of the frame would be 1518 bytes to 1522 bytes if the VLAN tag is present in the ethernet frame.
Let us know what is VLAN tag how the tagging and trunking 101 works. The IEEE 802.1Q is always referred to as the Dot1Q. It is a networking standard that mostly supports VLAN on the ethernet network. This networking standard tells a method in order to tag traffic between the switches. It tells which traffic belongs to which VLAN. To understand this concept in detail, let us take an example.

Let consider a simple switch 1 and a single computer A connected to the VLAN 10 and another single computer B connected to the VLAN 20. Take another switch 2 that we assign computer C to say as VLAN 10 and a computer D to the VLAN 20. Here we can say that computer C and Computer D belong to the VLAN 10 and computer B and computer D are connected to the VLAN 20.

These VLANs are local to each switch and the VLAN information cannot be passed between the switches. So we should link the two switches so that the computers are on the same VLAN can communicate.

This type of link we call the trunk. It can also be called the 802.1q link or can be called the Dot1Q link or simply we can call it the trunk link. This provides VLAN ID for the frames for traversing between the switches.

A trunk can be configured between the two switches or can be between a switch and the router. By the default mode, this trunk can able to carry the traffic from all the available VLANs to or from the switch. This can be configured to carry the specified VLAN traffic. The process that we traverse different VLAN traffic over the trunk is called trunking.

The main reason that a single link can become a trunk is not because of some of the special physical cable, but simply because of some of the configurations of the switch ports on both ends of the link.

Simply because of the configuration of the switch ports on the two ends of the link trunk port. Trunk port is the term of cisco, we call it the tagged port in the non-cisco world. Even the names are different it means the same thing.

A trunk port can add the VLAN tag for an ethernet frame in order to indicate which VLAN frame it indicates. The access port acts as the switch port that sends and expects to receive the traffic with the no VLAN tag.

We can also say that the access port carries traffic only for the one VLAN. To make the different VLAN traffic that travels across the two switches, we need a trunk, it is created by configuring the trunk ports. These trunk ports send and receive the tagged traffic. The access port can send and receive the untagged traffic.