VLAN

Virtual Local Area Network (VLAN) is a logical set of devices and users, which are not restricted by physical location and can be organized according to function, department and application, etc., and communicate with each other as if they are in the same network segment, hence the name VLAN. Since switch ports have two VLAN attributes, one is VLANID and the other is VLAN is a relatively new technology, which works in layer 2 and 3 of OSI reference model, and a VLAN is not necessarily a broadcast domain. A VLAN is not necessarily a broadcast domain, and the communication between VLANs does not necessarily require a routing gateway, which itself can form VLANs with different access control attributes through mutual permission of VLANTAG, which of course can also be done by routers at layer 3. However, through the permission of VLANID and VLANTAG, VLANs can structure logical topology and access control for almost any information integration system in a LAN. VLANs can provide a virtual network topology and access control functions for information services and sub-services, and between information services that match the service structure. Compared with traditional LAN technology, VLAN technology is more flexible and has the following advantages: reduced management overhead for moving, adding and modifying network devices; control of broadcast activities; and improved network security.