Route Selection Protocol Configuration

As a network administrator. Vro configuration is indispensable. However, different routing modes have different effects on the network. Here we need to have some knowledge about the routing protocol. Today, we will introduce the knowledge and configuration of the routing protocol. Addressing is implemented through a routing algorithm. The routing algorithm adds different information collected to the routing table, while forwarding is performed through the route table. Routers communicate with each other, update, and maintain the route table, the communication between routers involves the routing protocol ｡

The routing protocol mainly consists of static routes and dynamic routes. Static routes are manually input by the network administrator. Dynamic routes: the routing protocol is used to automatically adapt to changes in network topology or traffic. Static Routing has the advantages of simplicity, efficiency, and high priority ｡

Static route Configuration:

Router (config) ip route + non-direct connection CIDR block + subnet mask + next hop address

Router (config) # exit

Dynamic Routing can be divided into internal gateway protocol (IGP) and external Gateway Protocol (BGP) based on whether it is used in an autonomous system. Common internal gateway protocols include RIP and OSPF, the external gateway protocol has BGP, BGP-4, here mainly talk about the Internal Gateway Routing protocol: RIP (Routing Information protocol) is a distance vector Routing protocol, because it is simple, reliable, and easy to configure, it is widely used. However, because it supports a maximum of 15 hops and 16 hops are inaccessible, it is only suitable for small networks, in addition, its route information broadcast once every 30 s is also one of the important reasons for the network broadcast storm ｡

RIP Configuration:

Router (config) # router rip

Router (config-router) # network-number

Network_number is the direct connection CIDR Block of the vro.

Due to the limitations of RIP, A New Routing Protocol emerged: IGRP, IGRP (Interoor Gateway Routing Protocol) IGRP broke through the 15-hop limit, the work mechanism of RIP and IGRP, the preferred protocol for large-scale CISCO networks at that time, is to regularly update routes from all configuration interfaces. However, RIP is measured by the number of hops; IGRP uses multiple factors to establish optimal routing paths; Bandwidth, latency, Reliability, and LOAD) but its disadvantage is that it does not support VLSM and discontinuous subnets ｡

IGRP Configuration:

Router (config) # router igrp 100 (100 is the autonomous system number)

Router (config-router) # network-number

Router (config-router) # exit

Note:

1) The valid range of the serial number is 1-65535. The serial number is used to determine the vrouters and interfaces with the same regional serial numbers;

2) routers with different numbers do not participate in route update ｡

Enhanced Interoor Gateway Routing Protocol is the most typical balanced Hybrid Routing Protocol. It integrates the advantages of Distance Vector and link state Routing selection protocols and uses the scattering update algorithm, high routing performance can be achieved. It is characterized by irregular updates, that is, only some update routes are sent when the router changes the metering standard or the topology changes. VSLM supports variable length subnet mask, the routing information can be seamlessly exchanged between the autonomous system number and the IGRP:

Router (config) # router Kerberos (100 is the autonomous system number)

Router (config-router) # network

Network-number router (config-router) # exit

OSPF

OSPF is a link status routing protocol. The so-called link status refers to the status of the router interface, such as UP, DOWN, IP, network type, and other link status information through the link status announcement (LSA) each vro released to the Internet. Each vro establishes a topological database about the network through the LSA information, which can be used in a large network and supports VLSM using bandwidth as a measurement value, fast Convergence, efficient network management through partitioning ｡