What is a V-LAN?How it works?

Answer 1

A virtual LAN, commonly known as a vLAN or as a VLAN, is a logically-independent network. Several VLANs can co-exist on a single physical switch.

A VLAN consists of a network of computers that behave as if connected to the same wire - even though they may actually be physically connected to different segments of a LAN. Network administrators configure VLANs through software rather than hardware, which makes them extremely flexible. One of the biggest advantages of VLANs emerges when physically moving a computer to another location: it can stay on the same VLAN without the need for any hardware reconfiguration

Answer 2

vlans are used to create broadcast domains. so a switch provides electrical isolation between all of the computers plugged into the switch's ports. that solves the issue of collisions on a shared ethernet segment. but since switches are layer 2 devices (generally speaking), they don't provide a method for isolating broadcast. broadcast typically need to be seen by a group of computers (thats why the're broadcast), but may not need to be seen by all of the computers. segmenting at layer 3 provides that broadcast isolation, but raouters are layer 3 devices not switches.

so if you have a large switched network you end up with far too much overhead from broadcast being sent to every switch port. but you can provide isolation by creating groups of switch ports that are all members of a different vlan group.

so if i create a vlan, vlan 2, and i assign switch ports 1-4 to vlan 2, then broadcast coming from any of those ports (1-4) will bee sent to the other 3 ports, but not to any other ports. so if we also have ports 5-8 assigned to vlan 3, none of those ports would see the broadcast.

think of a vlan as an ip subnet - historically all computers attached to a switch had to be members of the same ip subnet, but with vlans ip subnets can span many ports on many different switches.

Answer 3

Vlan

Cirtual LAN

it becosme one LAN

all vlan members belong to one LAN
u cnan chage the port to anoterh vlan
and it will belongs to anotehr vlan
somany VLANs can exist on one physical LAN