Network Technology Learning Note 4-Routing

A router is a layer-3 device that connects different subnets.

Generally, a vro has a WAN port and a LAN port. Therefore, the corresponding vro has two addresses: one is the address of the same network segment as the LAN, and the other is the external address.

The router must be used in pairs, that is, the LAN port of the router is connected to the host of the LAN, and the WAN port is connected to the outside router. When you access the Internet, your request is forwarded to another vro through your vro,

The other router then forwards your request to the destination based on the route table.

So what is a route table? The route table is equivalent to a guide card, which indicates where to go and where to go. Each router will have a route table under maintenance.

On Windows, you can run the route print command to display the route table of the local machine.

Default route: 0.0.0.0 indicates any address. The last route entry is the path not specified in the route table. In the routing table printed by the route print command, you can see this one,

The corresponding gateway is the gateway that you usually use to access the Internet. (If you have wireless or wired Internet access, there will be two default routes. Which port does it go through? You can check the value of metric, who is the minimum)