Describes how to set static routes.

The following describes how to set static routes. You may have heard about static route settings. How can we use static route settings to make it easier? The following is a detailed introduction.

Static route setting instance: you may find that the last inductive route contains all the two subnets 192.168.0.0 and 192.168.1.0 under R1 ), but it also contains some subnets 192.168.2.0 ~ that do not actually exist in R1 ~ 192.168.255.0 ). If the subnet 6 exists under another vro in the LAN and the subnet 192.168.2.0 exists under R4), the route will fail. Therefore, this summary route is an inaccurate summary.

We all know that IPv4 addresses are composed of four 8-bit binary numbers, one is the network bit, and the other is the host bit. The subnet mask network bit is the binary number of all 1, and the host bit is the binary number of all 0. When each information packet passes through a vro, it checks its destination IP address and performs the & #8220; and & #8221; Operation with the subnet mask of the route entry in the routing table, and compare it with the destination IP address in the route entry. If the IP address is the same, it is forwarded according to the routing rule. If the IP address is different, check and compare the next one.

The static route settings show that the route summary operation is to extract the network bits with the same destination IP addresses from Multiple Route entries and write them into one. In this example, the reason why the summary route in section 3 is not accurate is that the same part cannot be all proposed. In Example 3, the first IP address on R3 is 192.168.0.0, and the second IP address is 192.168.1.0. We have extracted only the first two segments of 192.168, and the third segment of the network bit still has the same part.

In 192.168.0.0, the third part is written as a binary number of 000000008 bits 0), and in 182.161.0, the third part is written as a binary number of 000000017 bits, 0 bits, 1). Then their first seven digits are the same, the corresponding subnet mask should be 111111107-bit, 254-bit, 0), and the synthetic decimal value is.

Therefore, this summary route should be written as follows: the destination IP address is 192.168.0.0, The subnet mask is 255.254.0, And the next hop is 10.1.1.2. In this way, this summary route contains only two subnets: 192.168.0.0 and 192.168.1.0. It is a precise summary route. In section 6, the 172.16.0.0 host under R3 is sent to the information package of the 192.168.2.0 network segment, and the third network bit is written as the first 6 0 bits of binary 00000010 ), it is not included in this precise summary route.

In this case, the static route entry on R3 should be:
◆ Destination IP address 192.168.0.0, subnet mask 255.254.0, Next Hop 10.1.1.2.
◆ Destination IP Address 192.168.2.0, subnet mask 255.255.0, Next Hop 10.1.1.4.

When collecting routes, we should try to use accurate summary entries as much as possible. In line with the principle that the total entries can be aggregated, entries that cannot be accurately summarized will not be aggregated. In this way, route tables can be added and modified in a more organized manner in the future expansion and change of the network, reducing the chance of errors.

Summary of static route settings: Static Routing is easy to troubleshoot because it is easy to set up and stable in a network that is not frequently changed, therefore, Static Routing is also used in small and medium-sized enterprises and even some large campus networks. It is very common in practical applications and is a basic knowledge of network workers. As described in this article, the setting principle of Static Routing is relatively simple, but it can be said that it is the basis for learning various routing protocols and is a required part for learning routing knowledge.

Static Routing settings. In addition, the more complex the network, the more effective the summary route is, the more efficient the routing can be summarized and summarized, are closely related to the distribution of IP address segments in the network structure. The more continuous and organized the IP address deployment, the easier and more effective the route summary. Therefore, we should pay attention to systematic addressing when deploying the network. Note: In a subnet environment, routing induction is most effective when the network address is a continuous block in the form of 2 .)