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Name: Haidar Abdullah

ID: 202620092
 Introduction about VlAN
 Benefits of VLANs
 Configuring ports
 Define IEEE 802.1Q
 Configured VLAN
 Trunking operation
 VTP operation
 Deleting VLANs
 A VLAN is a logical group of network devices that
appears to be on the same LAN.
 Logically segment LAN into different broadcast
domains VLANs can logically segment users into
different subnets(broadcast domains).
 Broadcast frames are only switched on the same
Benefits of VLANs
 Help to control traffic
 Provide extra security(only devices belonging to the
same VLAN can communicate with each other.
 Ease the change and movement of devices.
Configuring ports
 Access ports are used when:
 Only a single device is connected to the port
 Multiple devices(hub) are connected to the port all
belonging to the same VLAN
 Another switch is connected to this interface, but this
link is only carrying a single VLAN(non-trunk link)
 Trunk ports are used when:
 Another switch is connected to this interface, and this
link is carrying multiple VLANs(trunk link)
Configuring ports
IEEE 802.1Q
 Significantly less overhead than the ISL
 802.1Q inserts only an additional 4 bytes into the
Ethernet frame.
 The 802.1Q tag is inserted by the switch before
sending across the trunk.
 The switch removes the 802.1Q tag before sending it
out a non trunk link.
IEEE 802.1Q
Configured VLAN
Trunking operation
• Trunking protocols were developed to
effectively manage the transfer of frames
from different VLANs on a single physical

• The trunking protocols establish
agreement for the distribution of frames
to the associated ports at both ends of the

• Trunk links may carry traffic for all
VLANs or only specific VLANs.
VTP Operation
 VTP switches operate in one of three modes:
 Server
 Client
 Transparent

• VTP clients cannot create, modify, or delete VLAN information.
• The only role of VTP clients is to process VLAN changes and send VTP messages out all
trunk ports.
• The VTP client maintains a full list of all VLANs within the VTP domain, but it does not
store the information in NVRAM.
• VTP clients behave the same way as VTP servers, but it is not possible to create, change,
or delete VLANs on a VTP client.
• Any changes made must be received from a VTP server advertisement.

• Switches in VTP transparent mode forward VTP advertisements but ignore
information contained in the message.

• A transparent switch will not modify its database when updates are received, nor will
the switch send out an update indicating a change in its own VLAN status.

• Except for forwarding VTP advertisements, VTP is disabled on a transparent switch.

• There is also an “off” VTP mode in which switches behave the same as in the VTP
transparent mode, except VTP advertisements are not forwarded.

• VTP servers can create, modify, delete VLAN and VLAN configuration parameters
for the entire domain.

• VTP servers save VLAN configuration information in the switch NVRAM. VTP
servers send VTP messages out to all trunk ports
Deleting VLANs
 The command below is to remove a VLAN from a
 Switch#vlan databasa
 Switch(vlan)#no vlan 300
Deleting VLANs
 Steps to assign a switch port to a new VLAN
Deleting VLANs