Understanding of static routes and default routes

A static route can be understood as a route to a specific destination, with a specific destination network address

If a specific destination address is not specified, the default route is gone.

The default route, also known as the default route , is a special static route with the destination address and mask configured as full 0 (0.0.0.0 0.0.0.0). When all routes in the routing table fail, the default route is used in order for the message to have a final sending point.

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Instruction explanation: IP route 192.168.3.0 255.255.255.0 192.168.2.2

On the hosta, the router sees the packet with the destination segment as 192.168.3.0 and sends the packet to the 192.168.2.2

Note 2:ip Route points to one, if all two are fitted, that means the packet is sent out from the FA0/1, and the other says the packet is sent to this IP (for example, 192.168.2.2). Two repetitions. Generally we set to point to IP.

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1) Why do I have a default route

Routing to view the routing table and decide how to forward the packet, with static routing configuration, cumbersome and error-prone. If the router has a neighbor who knows how to get to all the destinations, it can give the routing table matching task to it, saving a lot of things.

example, the gateway knows all the routes, and if a router is connected to the gateway, it can configure the default route to forward all packets to the gateway.

2) Why the default route is 0.0.0.0

When the IP address is matched, 0 represents wildcard, and any value can. Therefore, 0.0.0.0 and any destination address matching will succeed, resulting in the effect of the default route requirements.

Understanding of static routes and default routes