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05 January 2011 Page 1

LAB SHEET (03)

Routing: Default Routing Method

Understanding the problem:

Here in the above Picture we see that the Router is able to ping on the PC and to the

ISP IP address (68.110.171.97) because they are directly connected, the problem here is

when the Router Ping to any internet site it wont ping although we can ping on the IP

address of the ISP (Internet Service Provider).

So if you ping from the Router 1 to 68.110.171.97, then there will be a reply back. But

if you ping on IP address for example Google Web site, it will not ping and the success

rate is 0 (no reply back) because it doesnt know about the internet route, for example

ping 72.14.20.7.99 ; there will not be any reply.

This is due to the Router hasnt learned yet how to access the internet, NOW how I can

get all the route of the entire Internet on the whole Planet??!!

This can be solved by using Default route method; where you tell the router any

network you want to reach and you dont know how to reach it, please send it over

this IP, so you can do that by using like below command

R1(config)#ip route 0.0.0.0 0.0.0.0 68.110.171.97

What this command Says is send any IP address with any Subnet Mask to that ISP IP

address if you dont have a specific route in your routing table.

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05 January 2011 Page 2

To find any website IP address, you can do that by ping then the website name in your

command-line program, but in CISCO IOS you have to enable that by using the

following ;

R1(config)#ip name-server 4.2.2.2

DNS server is going to look up the website name and find out its IP address ( for

example; ping www.google.com), we configuring the router to look for the DNS server

(4.2.2.2) whenever there is translating from internet site name to IP address.

NEW Scenario:

Now we will combine the two pieces now, lets make ENG Router be able to reach to

R1 and R2 Networks, by using static routing.

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05 January 2011 Page 3

Dynamic Routing

Type of Routing Protocols:

1. Distance Vector:

Easy to Configure Not many Features (means if there is a problem in the Network, Distant

Vector is Slow in detecting that)

Protocols Example: RIP & IGRP, (RIP Protocol works well in smallerenvironment & IGRP too.)

2. Link State:

Difficult to Configure (More Knowledge Required). Feature-Riffic (means they support every Feature in the Network they need).

Protocols Example: OSPF & IS

IS

3. There is another one used more by CISCO routers, called Hybrid ( the best of both

classes above), example of this (EIGRP)

RIP:

Algorithm first Developed at 1969 RIP comes in two Versions: RIP V1 & RIP V2, but Today we only use RIP V2

RIPV1:

1. Classfull version2. No Authentication3. Uses Broadcast

RIPV2:

1. Classless Version2. Authenticated3. Multicast

Configuring RIP:

From the scenario above start configuring the Router with RIP V2:

Start with R1; first of all check the Routing Table to be sure there is no Previous

Configuration still exists (show ip route)

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