VLAN Technology Entry

VLAN is short for Virtual Local Area Network. On the one hand, VLAN is built on the basis of LAN switches; on the other hand, VLAN is the soul of LAN. This is because VLAN users can easily move and quickly build a broadband network in the network without changing any hardware and communication lines. In this way, the network administrator can logically allocate users and network resources without considering the physical connection method. VLANs fully reflect the important features of modern network technology: high speed, flexibility, easy management, and easy expansion. Whether VLAN functions are available is an important indicator for measuring LAN switches. Network virtualization is the trend of network development in the future.
VLAN is no different from common LAN in principle. However, from the perspective of user usage and network management, the most basic difference between VLAN and common LAN is as follows: a VLAN is not limited to a certain network or physical range. users in a VLAN can be located anywhere in a park, or even in different countries.
VLAN has the following advantages::
Control broadcast storms on Networks
VLAN technology is used to route a switch port to a VLAN. The broadcast storm of a VLAN does not affect the performance of other VLANs.
Ensure network security
Shared LAN makes it difficult to ensure network security because users can access the network by inserting an active port. The VLAN can restrict access by individual users, control the size and location of the broadcast group, and even lock the MAC address of a device. Therefore, the VLAN can ensure network security.

Simplify Network Management
Network administrators can use VLAN Technology to easily manage the entire network. For example, to build a working group network for a project, its members may be all over the country or the world. At this time, the network administrator only needs to set up a few commands to establish a VLAN network for the project within several minutes, its members use VLAN networks, just like local LAN. VLAN classification mainly includes the following types:
Port-based VLAN
Port-based VLAN is the simplest and most effective way to divide a virtual LAN. This is actually a set of some switching ports. The Network Administrator only needs to manage and configure the switching ports, no matter what device the switch port is connected.
MAC address-based VLAN
Because only the network adapter is assigned a MAC address, VLAN division by MAC address actually refers to dividing some workstations and servers into a VLAN. In fact, this VLAN is a set of MAC addresses. The VLAN is automatically recognized when the device moves. Network Management needs to manage and configure the MAC address of the device. Obviously, when the network size is large and there are many devices, the management will be difficult.

Layer-4 VLAN
VLAN 3rd is a common method used in Routers: IP subnet and IPX network number. The LAN switch allows a subnet to expand to multiple LAN switching ports, and even allows a port to correspond to multiple subnets.
Policy-based VLAN
Policy-based VLAN is a flexible and effective VLAN division method. What is the core strategy of this method? Currently, common policies are related to vendor device support ):
By MAC address
By IP Address
By Ethernet protocol type
Network-based applications