What is a VLAN

What is a VLAN ? VLAN, which is an abbreviation for the English virtual local area network, in Chinese called "Dummy LAN", a VLAN is a logical division of Local area network (LAN) devices (note, not physically) into a network segment (or smaller LAN LAN), Thus realize the virtual Workgroup (unit) data exchange technology. VLAN this emerging technology is mainly used in switches and routers, but the current mainstream applications are still in the switch. However, not all switches have this capability, and only three-tier switches have this capability.

　　The benefits of VLANs are mainly three:

(1) Separation of ports. Even on the same switch, ports that are in different VLANs are not able to communicate. Such a physical switch can be used as a switch for multiple logic.

(2) Security of the network. Different VLANs cannot communicate directly, which eliminates the security of broadcast information.

(3) Flexible management. Changing the network to which the user belongs does not have to change ports and wires, just change the software configuration.

The advent of VLAN technology enables administrators to logically divide different users within the same physical LAN into different broadcast domains based on actual application requirements, each of which contains a set of computer workstations with the same requirements, with the same properties as the physically formed LAN. Because it is logically divided, not physically, the workstations within the same VLAN are not confined to the same physical range, i.e. these workstations can be in different physical LAN segments.

　　What is a VLAN ? The VLAN features that broadcast and unicast traffic within a VLAN are not forwarded to other VLANs, which helps to control traffic, reduce device investment, simplify network management, and improve network security. In addition to the network can be divided into multiple broadcast domain, so as to effectively control the occurrence of broadcast storms, and make the network topology becomes very flexible advantages, but also can be used to control the network of different departments, different sites between the mutual access.

Citation: http://product.pconline.com.cn/itbk/wlbg/network/1107/2474493.html

What is a VLAN