What do you mean by layer 1 switches, layer 2 switches, and layer 3 switches?

Layer 1 switches support only physical layer protocols.

Layer 2 switches support physical layer and data link layer protocols, such as Ethernet switches. Layer 3 switches support physical layer, data link layer, and network layer protocols, such as some switches with routing capabilities.

In terms of ISO/OSI's layered structure, switches can be categorized as Layer 2 switches, Layer 3 switches, and so on.

Layer 2 switches refer to the traditional work in the OSI reference model of the second layer - the data link layer on the switch, the traditional routers and external switches can be used together to solve this problem, but now the processing speed of the router can not keep up with the bandwidth requirements. Therefore Layer 3 switches, Web switches, etc. came into being.

Three layer switch is a device with three layers of switching functions, that is, with the third layer of routing functions of the second layer of the switch, but it is an organic combination of the two, and is not simply a router device hardware and software superimposed on the LAN switch.

Network switch role:

Connecting the same type of network, when the network scale expansion, simply by extending the network cable has become unrealistic. And for different LANs, to realize the data transmission between each other, *** enjoy the resources of the network, there is a need for special connection equipment to achieve network expansion. At the same time, the increase of sites in the network, geographic expansion, the growth of business, prompting the rapid development of network interconnection.

The rapid development of network interconnection, resulting in the emergence of network switching technology, network switches also came into being. Broadly speaking, a switch is a device that accomplishes the function of information exchange in a communication system.

Interconnecting different types of networks, the switch can not only connect the same type of network, but also play a role in interconnecting different types of networks (such as Ethernet and Fast Ethernet).

Providing fast network services. Sometimes, in order to provide faster access, we can connect some important network computers directly to the switch's ports. In this way, the key servers and important users of the network have faster access speeds and support greater information traffic.