Virtual LAN: Introduction on VLAN, Types of VLANs and VLAN Characteristics

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  • Introduction on VLAN
  • Working with examples
  • Types of VLANs
  • Characteristics
  • Advantages

Introduction on VLAN

  • VLAN stands for ‘Virtual Local Area Network’ .
  • It is a subnetwork, or a segment of a local area network configured by software, not by physical wiring.
Title: Introduction on VLAN
  • Reason for segmentation is to make broadcasting possible at the Data Link Layer.
  • The stations in each segment from a group that can be the recipient of a broadcast message.
  • The message can come from some station in the group or from another outside of the group.
  • The idea of VLAN technology is to divide a LAN into logical, instead of physical, segments.
  • The group membership in VLAN՚s is defined by software, not hardware.

Example: If a person moves from one group to another, there is no need to change the physical configuration.

Two Switches in a Backbone Using VLAN Software

Title: Two Switches in a Backbone

Types of VLANs

  • A Protocol VLAN- which has traffic handled based on its protocol.
  • Static VLAN- also referred to as port-based VLAN, needs a network administrator to assign the ports on a network switch to a virtual network.
  • Dynamic VLAN- allows a network administrator just to define network membership based on device characteristics, as opposed to switch port location.

VLAN Characteristics

  • Membership: Different vendors use different characteristics such as port number, MAC addresses, IP addresses, etc.
  • Port Number: some uses switch port number as a membership.
  • MAC addresses
  • Combination
  • Combination between switches
    • Time-Division Multiplexing (TDM)
    • Frame Tagging
  • IP Addresses
  • Multicast IP Addresses


  • Manual Configuration
  • Automatic Configuration
  • Semiautomatic Configuration


  • Reduce cost
  • Reduce time
  • Creating virtual workgroups
  • Security
  • Reduce network traffic


Q1. VLAN technology divides a LAN into________ segments.

  1. Physical
  2. Logical
  3. Multiplexed
  4. Framed

Answer: B. Logical

Q2. In a VLAN, the stations are separated into groups by________ .

  1. Physical methods
  2. Software methods
  3. Locations
  4. Switches

Answer: B. Software Methods


#How it works

#Types of VLANs