Simple routing protocol Analysis and configuration

We all know that the function of the router is primarily addressing and forwarding addressing is the routing algorithm that is implemented by routing algorithms to add the different information collected to the routing table, and forwarding is through routing tables for mutual communication between routers updating and maintaining the routing table and routers communicating with each other involves routing protocols.

Routing protocols are mainly divided into static routing and dynamic routing

Static routing: Manually entered by the network administrator.

Dynamic routing: Automatically adapts to network topology or traffic changes through routing protocols.

The advantage of static routing is that it is simple, efficient, high priority

Configuration of static routes:

Router (config) IP route + non-direct network segment (popular is except for your s and e-port) + Subnet mask + Next hop address

Router (config) #exit

Dynamic routing can be divided into internal Gateway Protocol (IGP) and External Gateway Protocol (BGP) according to whether it is used within an autonomous system.

Common internal gateway protocols have RIP OSPF and other external gateway protocols have BGP BGP-4 here's the main next internal Gateway protocol

RIP (Routing Information Protocol) is a distance vector selection routing protocol because it's simple and reliable and easy to configure, so it's widely used but only for small networks because it supports a maximum number of hops for 15,16 And it is one of the most important reasons for the network broadcast storm that it broadcasts every 30S times.

Configuration of RIP

Router (config) #router rip

Router (config-router) #network Network-number

Network_number is a direct-connected segment of a router

Due to the limitations of RIP a new protocol emerged IGRP

IGRP (Interoor Gateway Routing Protocol) IGRP, as a result of breaking the 15-hop limit, became the preferred protocol for the large Cisco network at the time to work with the RIP and IGRP, which periodically issued routing updates from all configuration interfaces. However, RIP is measured by the number of hops, igrp the optimal route by multiple factors, bandwidth (bandwidth), latency (Delay), Reliability (reliability), load (load), etc. but its disadvantage is that it does not support VLSM and discontinuous subnets.

IGRP configuration:

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

Router (config-router) #network Network-number

Router (config-router) #exit

Attention:

1 The valid range of the number is 1-65535, the number is used to determine a set of regions with the same number of routers and interfaces

2 different numbers of routers do not participate in routing updates

EIGRP (Enhanced Interoor Gateway Routing Protocol)

EIGRP is the most typical balanced hybrid routing protocol, which combines the advantages of two routing protocols of distance vector and link state, and uses scatter update algorithm to achieve high routing performance.

The EIGRP feature is an unscheduled update that sends a partial update route only if the router changes metrics or the topology changes. Supports variable eldest subnet mask VSLM, with the same autonomous system number between EIGRP and IGRP, can seamlessly exchange routing information.

The configuration of EIGRP is approximately the same as that of IGRP:

Router (config) #router EIGRP (100 for Autonomous system number)

Router (config-router) #network

Network-number Router (config-router) #exit

Ospf

OSPF is a link state routing protocol The so-called link State refers to the state of the router interface, such as UP,DOWN,IP and network type, such as link state information published through the Link Status Bulletin (LSA) to the Internet each router each router through the LSA information to establish a network topology database Can be used in a large network and it supports VLSM use of bandwidth as a measure of convergence fast efficient network management through partitioning

OSPF configuration:

Router (config) #router OSPF 3 (3 is the process number)

Router (config-router) #network + Direct-connected network segment + Direct-connected network segment + Subnet mask (inverse code is wildcard) + area number (the area number must be the same when multiple routers are configured)

Router (config-router) #exit

Multiple router configurations If you choose the same process number, it can theoretically cause a conflict, but the actual test is the same.

These are the more common routing protocols and configurations. Personal understanding only for the little rookie like me. Reference