You can define a local area network (LAN) as a broadcast domain. Hubs, bridges, and switches in the same physical segment or segments connect all end nodes. End nodes can communicate with each other without a router. Routers connect LANs, routing the traffic to each appropriate port.
A virtual LAN (VLAN) is a local area network that maps devices on a basis other than geographic location, for example, by department, type of user, or primary application. Traffic that flows between different VLANs must go through a router, just as if the VLANs are on two separate LANs.
A VLAN is a group of network devices (computers, servers, and other resources) that behave as if they are connected to a single network segment, even though they might not be. For example, the marketing personnel might be located throughout a building, yet if they are all assigned to a single VLAN, they can share resources and bandwidth as if they are connected to the same segment. The resources of other departments can be invisible to the marketing VLAN members, accessible to all, or accessible only to specific individuals, depending on how you set up the VLAN.
VLANs have a number of advantages:
- VLANs let you easily segment your network. You can group users who communicate most frequently with each other in a common VLAN, regardless of physical location. Each group’s traffic is contained largely within the VLAN, reducing extraneous traffic and improving the efficiency of the whole network.
- VLANS are easy to manage. You can quickly add or change network nodes and make other network changes through the switch web management interface rather than from the wiring closet.
- VLANs provide increased performance. VLANs free up bandwidth by limiting node-to-node and broadcast traffic throughout the network.
- VLANs enhance network security. VLANs create virtual boundaries that can be crossed only through a router. Therefore, you can use standard, router-based security measures to restrict access to a VLAN.
For more information about VLANs, see the following knowledge base articles:
- How does a VLAN work on a smart switch?
- What is a management VLAN?
- What do I need to know about setting up VLANs?
Last Updated:04/17/2023 | Article ID: 24720
