- A VLAN is a switched network that is logically segmented by functions, project teams, or applications without regard to the physical location of users.
- For example, several end stations might be grouped as a department, such as engineering or accounting.
- Also, When the end stations are physically located close to one another, you can group them into a LAN segment.
- If any of the end stations are in different buildings (not the same physical LAN segment), you can then group them into a VLAN.
VLANs provide the following features:
Simplification of end-station moves, adds and changes
- When an end station physically moved to a new location, its attributes can reassign from a network management station through Simple Network Management Protocol (SNMP) or through the user interface menus.
- Moreover, When an end station moved within the same VLAN, it retains its previously assigned attributes in its new location. When an end station moved to a different VLAN, the attributes of the new VLAN applied to the end station.
Controlled traffic activity
- Virtual LANs allow ports on the same or different switches to grouped so that traffic confined to members of only that group.
- This feature restricts broadcast, unicast, and multicast traffic (flooding) only to ports included in a certain VLAN.
- The management domain is a group of VLANs that managed by a single administrative authority.
Workgroup and network security
- You can increase security by segmenting the network into distinct broadcast domains.
- Moreover, To this end, Virtual LANs can restrict the number of users in a broadcast domain.
- You can also control the size and composition of the broadcast domain by controlling the size and composition of a Virtual LANs.
Components Virtual LANs
Networks that have virtual LANs contain one or more of the following components:
- Switches that logically segment connected end stations
- Routers that provide VLAN communications between workgroups
- Transport protocols that carry VLAN traffic across shared LAN and ATM backbones
- Interoperability with previously installed LAN systems.