Lets understand this topic by asking questions to ourselves.
Q1. What is a VLan ??
In a simple language a virtual local area network (VLAN) is a logical group of workstations (or different network devices) that appear to be on the same LAN despite their geographical distribution.
A VLAN allows a network of computers and users to communicate in a confined environment as if they exist in a single LAN and are sharing a single broadcast and multicast domain.
Q2. Now why do we use VLANs ?
Some points to be noted about VLANs :
Q1. What is a VLan ??
In a simple language a virtual local area network (VLAN) is a logical group of workstations (or different network devices) that appear to be on the same LAN despite their geographical distribution.
A VLAN allows a network of computers and users to communicate in a confined environment as if they exist in a single LAN and are sharing a single broadcast and multicast domain.
Q2. Now why do we use VLANs ?
- VLANs are implemented to achieve scalability, security and ease of network management.
- Users don't have to be grouped physically together , they can be grouped logically using different vlan on a same switch thereby we are reducing the device cost too (if we never had this concept we need different devices for different groups.)
- The purpose of implementing a VLAN is to improve the performance of a network or apply appropriate security features.
Some points to be noted about VLANs :
- VLAN separates a Layer 2 switch into multiple broadcast domains.
- Individual ports of group of ports can be assigned to a specific VLAN.
- Only ports belonging to the same VLAN can freely communicate to each other.
- A router or layer-3 switch is need for inter VLAN communication.
- Broadcasts from one VLAN will never be sent out to ports belonging to another vlan.
- By default on a Cisco catalyst switches , all interfaces belong to VLAN is considered the management VLAN (by default)
