About the Gateway Understanding

Gateways (Gateway) are also known as inter-network connectors, protocol converters. The gateway realizes network interconnection above the network layer, is the most complex network interconnection device, only for two high-level protocol different network interconnection. Gateways can be used for both WAN interconnection and LAN interconnection. A gateway is a computer system or device that acts as a transformation task. A gateway is a translator that uses a different communication protocol, data format, or language, or even between two systems that have a completely different architecture. Unlike bridges, which simply convey information, the Gateway will repackage the information received to suit the needs of the intended system.

About the gateway say the points:

(1) The Gateway has two identities: internal LAN has an inside IP, external IP (external can be regarded as a public IP network);

(2) gateways, which are not equivalent to called network interfaces, are different concepts:

Gateway: Refers to the Intranet in all needs to access the external IP, all need to pass through this gateway, connected with the outside world. And the outside must go through this port, into the internal network. These two are often not the same address. all the IP in a network segment, there is only one gateway, but there are a lot of "network Interfaces".

Network interface: Generally select the first IP segment of the network as an intranet network segment of all the IP gateway (usually the end is 1, level 192.168.134.1), which is the network interface of the intranet. That is, in this routing table, all IP sent to this network segment is entered into this network segment through this "NET interface". The concept of a general network interface only appears in the "Routing table", and the "network interface" of different network segments in different routing tables must be different.

(3) The default gateway must be the IP address in the computer's own network segment, not the IP address in other network segments

The default gateway, which is all IP that accesses the extranet, is removed by forwarding it to this "gateway".

View current host's: Default gateway, and IP's Universal method:

C:\>route Print

There will be a route:

0.0.0.0 0.0.0.0Default gateway IP interface (machine IP) hop count

About the Gateway Understanding