Shulou(Shulou.com)06/01 Report--

VLAN (Virtual LAN), translated into Chinese, is "virtual local area network". Physically connected networks are divided into multiple logically independent virtual subnets. Originally, layer 2 switches can only build a single broadcast domain, but after using the VLAN function, it can divide the network into multiple broadcast domains.

Using the switch, the local area network can be divided into multiple VLAN. In general, the default VLAN of the switch is VLAN1.

Why can't routers be used to separate broadcast domains? 1, the router interface is limited; 2, the router can only divide the broadcast domain through the network interface.

Inter-VLAN communication: routing technology is required

Switch ports can be divided into the following two types:

Access Link (Access Link)

Aggregation Link (Trunk Link)

The VLAN division of a single switch is usually as follows:

L generate VLAN

Set the access link (determine which VLAN each port belongs to)

The method of setting the access link can be fixed in advance or dynamically change the setting according to the connected computer. The former is called "static VLAN", while the latter is naturally "dynamic VLAN".

Static VLAN, also known as port-based VLAN (Port Based VLAN). As the name implies, it is the setting method to specify which VLAN each port belongs to. 、

Dynamic VLAN is to change the VLAN to which each port belongs at any time according to the computer connected to each port. This avoids the above operations such as changing settings. Dynamic VLAN can be roughly divided into three categories:

L VLAN based on MAC address (MAC Based VLAN)

L subnet-based VLAN (Subnet Based VLAN)

L based on user's VLAN (User Based VLAN)

VLAN partition of multiple switches: aggregation link method (trunk link), attach VLAN attribute messages to v data frames, ports that can forward communications of multiple different VLAN.

VLAN relay enables data frames between the switch and the switch or between the switch and the router to be connected through this trunk line.

VLAN Relay Protocol (VTP) is used to simplify the management of VLAN in large switching networks. According to VTP, the operation mode of the switch is divided into three modes: server, client and transparent. The switch configuration can be created, deleted and modified in server mode, while it is not allowed to create, delete and modify switch in client mode. It can be configured in transparent mode and cannot be transmitted to other switches.

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.