Dynamic routing Description:
Dynamic routing is a concept opposed to static routing, the router refers to the own routing table can be established automatically in accordance with certain routing information exchange between routers, and can be automatically adjusted according to changes in a timely manner to links and nodes. When the link between the node or network fails, or the presence of other available routes, dynamic routing can choose the best available route itself and continues to forward packets.
RIP routing structure:
Use RIP messages listed items, RIP host can exchange routing information between each other. This information is stored in the routing table, routing tables for each one to know, to retain a reachable destination. Each destination entry is the lowest cost route to the destination.
Note the number of entries in each destination may vary with different routes manufacturers. Manufacturers may choose to comply with norms, standards can also be carried out as they see fit "enhanced." Therefore, users are likely to find a particular trademark router as a route to the destination stores each network is the same as the cost of up to four.
Each routing table entry includes the following fields:
destination IP address field
from - metric vector domain
next hop IP address domain
routing change flag domain
routing domain timer
noted that although RFC 1058 is an open standard, to support a large number of interconnected Network Address structure, however, it was designed by the IETF protocol within the autonomous system for the Internet. Thus, the use of this form of natural RIP is a network interconnection agreement.
Common dynamic routing protocols:
RIP: Routing Information Protocol (RIP) is an interior gateway protocol IGP protocol was first widely used. RIP is a distributed based on distance vector routing protocol, is the standard Internet protocol, its biggest advantage is simple, less overhead.
OSPF: OSPF is an interior gateway protocol is used for routing within a single autonomous system.
IS-IS: IS-IS routing protocol is a dynamic routing protocol originally ISO CLNP is designed.
BGP: Border Gateway Protocol (BGP) is in a kind of autonomous system routing protocol over TCP. BGP is the only protocol that is used to handle the size of the network like the Internet, is the only protocol that can deal well with having multiple connections to unrelated routing domains. ~~RIP dynamic routing configuration gymnastics
Experiment planning, dragged three routers and two PC in the operating area, and their interface IP planning, R1 is f0 / 1 interface 192.168.30.1/30,f0/0 interface 192.168.20.2/30 ; R2 is f1 / 0 interface 192.168.10.1/24,f0/0 interface 192.168.20.1/30;R3 of f1 / 0 interface 192.168.30.2/30,f0/0 interface 192.168.40.1/24;PC1 the IP address is the IP address 192.168.10.2/24;PC2 is 192.168.40.2/24.
Experimental topology
> Router and the PC interface configuration
R2路由器：
输入以下内容：
conf //进入全局模式
int f0/1 //进入f0/1接口
ip add 192.168.10.1 255.255.255.0 //配置f0/1接口网关
no shut //启动接口配置
ex //退出
conf //进入全局模式
int f0/0 //进入f0/0接口
ip add 192.168.20.1 255.255.255.252 //配置f0/0接口网关
no shut //启动接口配置
ex //退出
do show ip route //查看路由表
R1路由器：
输入以下内容：
conf
int f0/0
ip add 192.168.20.2 255.255.255.252
no shut
ex
conf
int f0/1
ip add 192.168.30.1 255.255.255.252
no shut
ex
do show ip route
R3路由器：
输入以下内容：
conf
int f0/1
ip add 192.168.30.2 255.255.255.252
no shut
ex
conf
int f0/0
ip add 192.168.40.1 255.255.255.0
no shut
ex
do show ip route
PC机
输入以下内容：
ip 192.168.10.2 192.168.10.1
ip 192.168.40.2 192.168.40.1
配置RIP动态路由
配置R2动态路由
输入以下内容：
router rip //启动RIP进程
network 192.168.10.0 //宣告主网络号
network 192.168.20.0 //宣告主网络号
version 2 //设置RIP为v2版本
no auto-summary //关闭路由自动汇总
ex //退出配置R1动态路由
router rip
network 192.168.20.0
network 192.168.30.0
version 2
no auto-summary
ex配置R3动态路由
router rip
network 192.168.30.0
network 192.168.40.0
version 2
no auto-summary
ex
Use command do show ip route view respectively R1, R2, R3 routing table.
Use the ping command to view PC1 and PC2 can communicate, in order to verify whether the dynamic routing configuration is successful.
