Division Basis of Layer 3 Switch, layer 2 switches Switch and Fool Switch

It is a three-layer switch that can be routed. Layer 2 switches has no routing function, but it can divide vlan and so on.

The fool switch just doesn't have any configuration. In a sense, you can see it as a hub.

Functionally, all the fool switches are in layer 2 switches, and all the layer 3 switches are in layer 2 switches!

Three-layer switching (also called multi-layer switching technology, or IP switching technology) is put forward relative to the traditional switching concept. As we all know, the traditional switching technology runs in the second layer of OSI network standard model-data link layer, while the three-layer switching technology realizes the high-speed forwarding of data packets in the third layer of network model.

Simply put, the three-layer switching technology is "two-layer switching technology+three-layer forwarding". The emergence of three-layer switching technology has solved the problem that the subnets in a local area network must be managed by routers after the network segments are divided, and solved the network bottleneck problem caused by the low speed and complexity of traditional routers. ?

The equipment with three-layer switching function is a layer 2 switches with three-layer routing function, but it is an organic combination of the two, rather than simply superimposing the hardware and software of the router equipment on the lan switches.

Extended data:

The switch works in three ways:

1. Straight-through Ethernet switch can be understood as a line matrix telephone switch with cross ports. When the input port detects a packet, it will check the packet header, get the destination address of the packet, and start internal dynamics. 、

The lookup table is converted into the corresponding output port, which is connected at the intersection of input and output, and the data packet is directly connected to the corresponding port to realize the switching function. Because there is no need for storage, the delay is small and the exchange is fast, which is its advantage. Its disadvantage is that data packets

2. Store and forward

Store-and-forward mode is the most widely used mode in the field of computer network. It checks the data packet at the input port, takes out the destination address of the data packet after processing the wrong data packet, and converts it to the output port through the lookup table to send the data packet.

Because of this, the store-and-forward method has a long delay in data processing, which is its deficiency, but it can detect the errors of packets entering the switch and effectively improve the network performance. More importantly, it can support the conversion between different speed ports and keep the cooperation between high-speed ports and low-speed ports.

3. No debris

This is a solution between the first two. It checks whether the packet length is 64 bytes. If it is less than 64 bytes, it means that it is a fake packet, and then it is discarded. If it is greater than 64 bytes, the data packet is sent. This method also does not provide data validation. Its data processing speed is faster than the store-and-forward mode, but slower than the straight-through mode.