A virtual local Area Network (VLAN) is a communication technology that divides a physical LAN into multiple broadcast domains logically.
Each VLAN is a broadcast domain. Hosts within a VLAN can directly communicate with each other, but cannot directly communicate with each other. In this way, broadcast packets are restricted to one VLAN..
Early Ethernet is a data network communication technology based on CSMA/CD (Carrier Sense Multiple Access/Collision Detection) sharing communication media. A large number of hosts can cause serious conflicts, broadcast flooding, performance degradation, and even network unavailability. Although Layer 2 devices can solve serious conflicts, they cannot isolate broadcast packets and improve network quality.
In this case, VLAN technology appears. In this technology, a LAN can be divided into multiple logical vlans. Each VLAN is a broadcast domain. The communication between hosts in a VLAN is the same as that in a LAN. As shown in the following picture..
Therefore, vlans have the following advantages:
● Restricted broadcast domain: The broadcast domain is restricted to one VLAN, which saves bandwidth and improves network processing capability.
● Enhances LAN security. Packets in different vlans are isolated from each other. That is, users in one VLAN cannot directly communicate with users in other vlans.
● Improves network robustness: faults are restricted to only one VLAN. Faults in this VLAN do not affect the normal operation of other vlans.
● Flexible construction of virtual workgroups: vlans can be used to assign different users to different workgroups. Users in the same workgroup are not limited to a fixed physical range, which makes network construction and maintenance more flexible.
Vlan technology is widely used in switch, ONU, OLT and other device communication.
The above is Shenzhen HDV Phoelectron Technology Ltd. bring customers about the VLAN introduction article, and our company is a specialized production of optical network manufacturers, the products involved ONU series (OLT ONU/AC ONU/CATV ONU/GPON ONU/XPON ONU), Optical module series (optical fiber module/Ethernet optical fiber module /SFP optical module), OLT series (OLT equipment /OLT switch/optical cat OLT), etc., there are various specifications of communication products for the needs of different scenarios for network support, welcome to consult.