RIP configuration of Dynamic Routing Protocol

A dynamic route is a process in which routers communicate with each other, transmit route information, and update the route table using the received route information. It can adapt to network structure changes in real time. If the route update information indicates that the network has changed, the route selection software recalculates the route and sends new route update information. This information allows routers to restart their routing algorithms and update their route tables to dynamically reflect network topology changes.

If dynamic routing is used, routers send their route information to the neighboring routers, receive the route information sent from the neighboring routers, and selectively Save the route information, generate your own route table.

Dynamic Routing Protocol Overview

Dynamic Routing is implemented based on a certain routing protocol. The routing protocol defines some rules for a router to communicate with other routers. That is to say, the routing protocol specifies how routers learn routing, and the criteria used to select routing and maintain routing information.

Dynamic Routing is like a language used between routers to exchange information. Through it, routes can share network connection information and status information. The dynamic routing protocol is not limited to updating the path and route table. When the Optimal Path to the target network fails, the dynamic routing protocol can be in the remaining available paths, select an optimal path for replacement.

Each routing protocol must have the following steps.

1. Route information to other routers.

2. Accept the routing information of other routers.

3. Calculate the optimal route to each target network based on the received route information and generate a route table.

4. respond to changes in the network topology in a timely manner, adjust the route to generate a new route table, and notify other routers of the topology changes in the form of route information.

Metric value: it is the reference value of the optimal route for routing protocol selection. Different routing protocols use different metric values. Sometimes, multiple metric values are used. The metric values are described as follows:

Hop count: You can simply record the hop count of a vro.

Bandwidth: Bandwidth Measurement selects a high-bandwidth path instead of a low-bandwidth path.

Load: The Load Measurement reflects the traffic usage of links along the route.

Latency: The time taken to measure the path of a data packet.

Reliability: the reliability measure is used to measure the likelihood of a link failure under certain circumstances.

Cost: a general term used to describe the advantages and disadvantages of a route. The minimum cost (maximum cost) or the minimum (maximum) it only refers to a view of the routing protocol on the path based on its specific measurement.

Dynamic Routing Protocol classification: Common routing protocols include distance vector routing protocol and link status protocol.

Distance Vector Routing Protocol: routes are selected based on the number of routers passing through the source network to the target network. The number of hops is used. Typical protocols such as RIP and IGRP.

Link Status Routing Protocol: the link status routing protocol selects routes from the source network to the target network, and uses multiple measurements. Typical protocols such as OSPF and IS-IS.

Configure dynamic route protocol RIP

The RIP protocol uses the number of hops as the unique measurement value. In RIP, the maximum number of hops is 15, and 16 hops are considered inaccessible. RIP uses UDP port 520. After the vro is started, route update information is sent from the interfaces of each initiated RIP Protocol every 30 s on average.

Shows how RIP works:

As shown in: the router receives the route information sent from the neighboring router and compares it with the entries in its route table. If the route table already contains this route information, the router will compare whether the new received route information is better than the current entry. If it is better than the current entry, the router will replace the original route entry with the new route information. Otherwise, the vro compares whether the route information and the original entry are from the same source. If the route information is from the same source, the route information is updated. Otherwise, the route information is ignored.

The RIP configuration command is as follows:

Router (config) # router rip

Router (config-router) # network-number

Network-number: the CIDR Block directly connected to the route.

For example, configure RIP on R1 and R2 to connect the two routers.

The R1 configuration is as follows:

R1 (config) # int f0/0

R1 (config-if) # ip add 10.0.0.1 255.0.0.0

R1 (config-if) # no sh

RR1 (config-if) # exit

R1 (config) # int f1/0

R1 (config-if) # ip add 202.106.123.1 255.255.255.0

R1 (config-if) # no sh

R1 (config-if) # exit

R1 (config) # router rip

R1 (config-router) # network 10.0.0.0

R1 (config-router) # network 202.106.123.0

R2 is configured as follows:

R2 (config) # int f0/0

R2 (config-if) # ip add 192.168.1.0 255.255.255.0

R2 (config-if) # no sh

R2 (config-if) # exit

R2 (config) # int f1/0

R2 (config-if) # ip add 202.106.123.2 255.255.255.0

R2 (config-if) # no sh

R2 (config-if) # exit

R2 (config) # router rip

R2 (config-router) # network 192.168.1.0

R2 (config-router) # network 202.106.123.0

In this case, you only need to configure the corresponding IP addresses on PC1 and PC2 and configure the gateway to ping each other.

You can use the show ip route or show ip protocols command to view route table and route protocol information.

Difference between RIP v1 and RIP v2

In the RIP dynamic protocol, there are two versions: version 1 and version 2. The difference is that version 1 can receive announcements sent by version 1 and version 2, however, version 2 can only receive notifications sent by version 2. In addition, version 1 has a classless routing protocol that does not carry a network mask when declaring route information. version 2 is a classless routing protocol that carries a network mask when declaring route information.

Version 1 does not support continuous subnets.

If version 2 is configured, route aggregation is not performed for each vro, because version 2 is automatically summarized by default.

The syntax for configuring version 2 is as follows:

Router (config) # router rip

Router (config-router) # version 2

Router (config-router) # no auot-summary

Router (config-router) # network-number

Auot-summary: Disable route aggregation.