Benefits of vlan

Find here the best and industry benefits of Vlan

1. BENEFITS OF VLAN

2. INTRODUCTION:
In a switched network there is always a single broadcast
domainwhich means every devicethat is attached to the switchwill
see the broadcast.
A VLAN or virtual local area networkremoves the physical barrierand
treats the host as if theywere all part of the same subnetwhile
logically separating networkswithin networks creatingsmaller
broadcast domains.
VLANS offer a number of advantagesover traditional LANS.

3. SIMPLIFIED ADMINISTRATION:
When a computer is physically movedto another location it can
stayon the same VLAN without anyhardware reconfiguration.
Performance:Using VLANS it reduces the sizeof that broadcast
domaintherefore improving efficiency.For example, if we take three
computersand we'll say that they are part of themanufacturing
group.We want to prevent manufacturing employees from viewing
YouTube videos.We can create a VLAN and isolate themfrom the
internet.The VLAN does not allow internet accessbut then is trunked
to the main network.

4. VLAN Security:
Can be used to restrict access.Security also provides setup
authenticationfor VLAN TrunkingProtocol and we canimplement
wireless constraintsby ensuring a user assigned to a specificVLAN will
always connect to that VLANregardless of their location. This isolation
gives the bonus of additional security.VLAN tags can also be
maintained between switches.Special ports called trunks are
configured on interfaces,carrying VLAN-tagged frames between
switches.This allows administrators to segregate traffic,not just within
a single switch, but also amongstthe entire enterprise.VLANs also
enable a practice called Router on a stick.A single physical router
interface connects to a switch.The router port is configured with
manyvirtual subinterfacesthat run on different VLANs.

5. LAN Segmentation:
Virtual local area networks are used tologically separate Layer 2 switch
networks.Users on different VLANs can't communicate directly,just as they would
if they were on physically separatenetworks.It's a great way to segment a
network, and improve security.
Cost:
Segmenting a large VLAN against a relatively smaller VLANs is economical
against creating a routed network with routers because normally routers costlier
than switches.
Physical Layer Transparency:
VLANs are transparent on the physical topology and medium over which the
network is connected.
This is an efficient way to connect alow port count router to multiple
subnets.VLANs are an integral part of every enterprise network,giving flexibility
and security.

6. Establishing VLAN memberships
Most frequent used approaches are discussed below:
Static VLANs or port-based VLANs.
Static VLAN assignments can be created by allocating ports to a
VLAN. As a device enters the network, the device automatically
assumes the VLAN of the port. If one changes ports and seeks
access to the same VLAN, the network administrator must manually
make a port-to-VLAN assignment for the new connection.

7. Dynamic VLANs:
Dynamic VLANs are created using software. With a VLAN
Management Policy Server (VMPS), an administrator can allocate
switch ports to VLANs dynamically based on information such as the
source MAC address of the device connected to the port or the
username used to log onto that device. As a device enters the
network, the switch queries a database for the VLAN membership of
the port that device is connected to.

8. Protocol-based VLANs: For switch which supports protocol-based
VLANs, traffic will be managed on the basis of its protocol. This will
segregate the traffic from a port based on the particular protocol
of defined traffic.
For example,
If a host generated traffic type ARP on a port A
A network with IPX traffic to port B
A router forwarding IP traffic to port C
If a protocol-based VLAN is created that supports IP and contains
all three ports, this prevents IPX traffic from being forwarded to ports
A and C, and ARP traffic from being forwarded to ports B and C,
while still allowing IP traffic to be forwarded on all three ports.