Definition of VLAN
VLAN is a layer 2 switching technology that separates layer 2 broadcast domains. Each host connected to the layer 2 switch creates a broadcast frame. In other words, an Arp request from one computer to another creates a layer 2 broadcast frame. It is like calling one of the people in a room. “Hey, Mg Mg,” I called my colleague not far away. The whole room will hear this. Who are you calling? We will be curious. Only Maung Maung will answer yes. This is how I released a broadcast. Both non-owners and non-owners heard it all. In the topology below, all computers in SALES and TECH are in the same broadcast domain, so both SALES broadcasts and TECH broadcasts are mixed in that network.
Why use VLAN?
If I had to talk to you in private. I do not want others to know. In that case, I would take him to a room. Then I have something to say. Then the rest of you will know and you can say whatever you want. This is called a VLAN. I mean, Maung Maung and I created a one-room broadcast domain. So security will be better. And for some, as a baby gets older, he or she will outgrow this. This is the main purpose of creating a VLAN.
You do not need to use any special devices to split the VLAN. There is no need to separate physical locations. You can split multiple VLANs in a single cisco switch. So people with the same VLAN will talk to each other. It does not make people unaware of VLAN and it does not bother them. In the topology below, the two broadcast domains are split. With SALES and TECH. So SALES broadcast will only go to SALES. TECH broadcast will only go to TECH.
Let me first explain the technical terms and functions you need to know before configuring VLAN.
Vlan trunking protocol – It is used to transport VLAN between two switches.
Is There are two types: Inter-Switch Link (ISL) and IEEE 802.1q. ISL is developed by cisco and 802.1q is a standard protocol defined by the IEEE.
The link between the two switches is the link that carries different Vlan traffic between the two switches, called the VLAN trunk. The protocol that controls the operation of the VLAN trunk is called the VLAN trunking protocol.
VLAN tagging – This is the process of attaching a layer 2 frame to a VLAN header so that the relevant VLAN traffic on the trunk does not mix with other VLAN traffic. So I think you know a little bit about the concept of VLAN.