Dynamic routing protocol: introduction to RIP

First, dynamic routing

(1), Dynamic routing Protocol Foundation

1, dynamic routing overview

Dynamic routing is the process by which routers in a network communicate with each other, transmit routing information, and update the routing table with the received routing information. It can adapt to the change of network structure in real time

If the routing update information indicates that the network has changed, the routing software recalculates the route and sends out new routing update information

If the router has an IP address configured for the interface, the direct-connected segment is stored in the routing table

If you use static routing, for a network segment that is not directly connected, you need to configure the next hop address on the router to reach the target segment, that is, you need to manually construct the routing table by specifying a path for data transmission.

If dynamic routing protocols are used, routers send their own routing information to neighboring routers, receive routing information from neighboring routers, selectively save the routing information, and generate their own routing tables

"As shown in the picture"

A.R1 will send direct-connected segment 10.0.0.0 and 20.0.0.0 information to R2

B.R2 can learn to 10.0.0.0 network segment, R2 will save 10.0.0.0 in their own routing table, but also send R3 10.0.0.0, 20.0.0.0 and 30.0.0.0 network segment information

C.R3 will be able to learn the 10.0.0.0 and 20.0.0.0 network segments

"Characteristics of dynamic Routing"

Dynamic routing is suitable for networks with large network size and complex network topology

A. Reduced management tasks: The process of dynamic routing is all done by the router itself, routing learning, routing forwarding, routing maintenance tasks are done by the dynamic route

B. Network bandwidth consumption: Because dynamic routing is the network information that every router that understands the network by communicating with other routers has to tell the other routers what they know. At the same time, from other routers to learn what they do not know the network information, which will inevitably send packets, and these routing packets will occupy a certain amount of network traffic

2. Dynamic routing protocol

"Dynamic Routing Association Overview"

The dynamic routing protocol is based on some kind of routing protocol (Routing Protocol).

The routing protocol defines some of the rules that routers communicate with other routers, that is, routing protocols that specify how routers are to learn routes, what criteria are used to select routes, and how to maintain the path information

A dynamic routing protocol is like a language used to communicate information between routers, through which routers can share network connection information and state information.

The dynamic routing protocol is not limited to the path selection and the updating of the routing table, when the optimal path of the destination network is problem, the dynamic routing protocol can choose the next optimal path to substitute in the remaining available paths.

"Routing algorithm several necessary steps"

A) delivery of routing information to other routers

b to receive routing information from other routers

c to compute the optimal path of each destination network based on the routing information received and generate the routing table

D timely response to changes in network topology, adjust routing to generate a new routing table, while the topology changes in the form of routing information to other routers to declare

"Measures"

When the same network segment is reached with two or two different paths, the dynamic routing protocol chooses an optimal path to transmit data.