What is a gateway? What's the use?

Gateways are also called gateways and protocol converters. Gateway realizes network interconnection above the network layer, and is the most complex network interconnection equipment, which is only used for interconnection of two networks with different high-level protocols.

Walking from one room to another is bound to go through a door. Similarly, sending information from one network to another must go through a "gateway", that is, a gateway. As the name implies, a gateway is a "gateway" for one network to connect to another. Which is a network checkpoint.

Extended data:

A gateway is essentially the IP address of a network to other networks.

For example, there are networks A and B. The IP address range of network A is "192.168.192.168.1.254", and the subnet mask of network A is 255. The IP address range of network B is "192.168.2.1~192.168.2.254" and the subnet mask is 255.255.0.

Without a router, there would be no TCP/IP communication between the two networks. Even if two networks are connected to the same switch (or hub), the TCP/IP protocol will determine that the hosts in the two networks are in different networks according to the subnet mask (255.255.255.0).

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