hello friends in this video tutorial we are going to talk about the two very commonly used network types that are lan and vlan plus i am going to explain you how the traffic flow in lan network and how broadcast traffic make your land network slow and also how the vlan rescue you from that situation so first i'm going to talk about the lan network lens stand for local area network basically lan is a computer network dead interconnect computer laptop or servers within a limited area such as home office or building in simple words lan network
is a group of devices such as laptop desktop or printer which are located in same building or in close proximity and connected to each other via switch the best example of lan network from our life is our home network where all users and devices are connected to a single switch or home isp device and all devices are on same ip scheme normally that is class i cip that is 192 168 1.1 or 192.168.0.1 series also in lan network broadcast packet are advertised on each and every device in length because lan network work on single broadcast
two main there are two primary lan types in networking field one is wildland and second one is wireless lan also called w line wide line also called ethernet lan and its most commonly used type in networking where switch and ethernet cabling used to connect endpoint devices such as pc printer server or desktop in home or office network but now in these days we are commonly using wireless lan where we use wireless communication instead of wide communication a wireless local area network will typically have a wireless router or access point for end devices in simple world
wireless local area network is a lan network but without using ethernet cables a wide or wireless local area network are useful or recommended for home or small business where only a handful of devices connected to each other via land switch but it failed in large local area network where hundreds or thousands of devices connected via lan switch and as we know ethernet lan is a shared medium so the amount of broadcast traffic which is head or received to all devices on the lan network can create traffic congestion and make the network slow this is the
time where we need to use the vlans in the network but before to understand the vlans it is very important to understand the flow of traffic in lan network also you need to know how the broadcast traffic affect the lan network here you can see we have a five pc that connected to a switch via ethernet cable and make a wide lan network the latest switch already know the ip address mac address and the port interface of each connected device what happened when pca want to send a packet to pcd in the lan network he
sent the packet to switch with source and destination mac address and switch the destination mac address in his database or mac table and after getting match forward the packet to the destination port but in second scenario if any pc send a packet to a switch with broadcast mac address or special microdesk status fff dot fff dot ffff switch will send that packet to the all interface on the switch because that is broadcast message and when any switch received the broadcast message it forward that packet to all interface except from where it receive it because this
lan network is a single broadcast domain network this is fine with small home or office network but in large organization if anyone send a broadcast or multiple pc send the broadcast in the network and pc forward that broker to all and every pc on the network it will make the network congestion and make your network slow second big issue in lan network is security all devices and pc connected to a single broadcast domain so all the devices in the network can see each other broadcast traffic and if any outsider or guest connect to the same
lan network he can see monitor and record the traffic that is big data security issue so now if you as a network engineer want to separate the network traffic as per department so the one department can't see any broadcast from other department or guest network can't see the office traffic the easiest way to accomplish this is by creating vlan by using vlan on vran capable switch you can divide the one switch in small chunks and can create separate virtual network and you can do this virtually not physically i hope so you understand the flow of
traffic in lan network and how broadcast traffic flow in the network now it's time to understand the vlan the vlan stand for virtual local area network will give us the benefit of physical separation of our network but we then do this virtually i will explain you vlan in this example where we have a single switch and couple of pc on different floor and they all connected to switch via ethernet cable as time pass and company size increase we just add the new switch on each floor and connect the end user to that switch via ethernet
cable and everything is working but as time pass employees start complaining about slow network or connectivity what happened when any pc send broadcast packet it go to each and every switch and pc in the network and when multiple users send the broadcast traffic that broadcast will go to each and every switch and every pc in my office network and make network congestion on all switches and make the network slow the solution of this issue is adding vlan capable switch and create vlans in vlan capable switch we need to create vlan and assign interface to specific
vlan then what happened only interfaces in same vlan can communicate to each other on same switch and broadcast traffic will not go out of that vlan for example in my office network there are three departments we say orange pc belong to account department green pc belong to sale and blue pc belong to hr department so i create three vlan in my switch we land 10 for account will and 20 for sale and vlan 30 for hr department then i will assign the interfaces to each vlan and after that i connect all account department pc to
account vlan cell department pc i connect to cell interfaces and etched button pc icon to hr interface on the switch so pc on same vlan can communicate to each other but other pc in different vlan on same switch can't see their traffic also in future if new employees join any department we just need to assign interface on switch and assign that department vlan so new pcs start communication with other devices in same vlan it's also very easy if we need to open whole new department in company we just need to create a new vlan and
assign interfaces to that vlan on same switch and create the pc that's it the broadcast traffic of each vlan will remain in selected ports or interfaces and will not go out of that vlan so here you can see vlan are very scalable and make very easy to control broadcast traffic by dividing single switch into small switches but virtually i think that is enough basic knowledge about vlan but still there is one issue as you know we create multiple vlan vlan 10 20 and 30 in our switch question is if interface can only communicate with other
interface in same vlan then which vlan interface do we assign to connect our second switch the answer of this problem is trunk port there are two type of ports in switch one is called access port and second one is trunk port when a switch port assigned to any vlan for example vlan 10 20 or 30 that port is called access port also you can say any switchboard who forwards single vlan traffic to end device is called access port and as per his name access port access port is designed for endpoint devices such as laptop pc
or server to access the network that's why it's called access port as you know the brand new cisco switch when we take out of the box they have a default vlan and that is vlan1 all interfaces on that switch are assigned to default vlan by factory setting its mean every interface can talk to each other by default on vlan 1 and they are access port mode the second type of port is trunk port as his name described trunk trunk code can carry traffic of multiple vlans trunks ports are used to send traffic between network devices
such as switch to switch or switch to router or server so when we have a multiple vlan on a switch we create transport on both switches and we allow all vlan to pass their traffic from that trunk port that's it for vlan and vlan thank you for watching my video and please don't forget to like and subscribe my channel
