Summary Route Practice Set 1

 In 200-301 V1 BBB Not in new books, CCENT-OLD, IPv4-Adv Summary Routes

Want proof you are ready for #CCNA? Try these route summary drills. The underlying skills require a fair amount of mastery of sub netting, so doing these drills can help prove you are ready for the toughest sub netting the CCNA has to offer.

This post lists three practice problems. Each problem lists a set of subnet/mask pair for existing routes in some router. Your job: choose the subnet/mask pair to use as the best summary route that includes the addresses in all the routes in the original list. Unsure as to what that means? Check out this post that explains more about route summarization.

Your task: Imagine that each column of Table 1 lists subnet/mask combinations that exist as routes in some router’s IP routing table. Your job: find the subnet/mask combination that you would configure in a manual summary route to replace all the routes with one summary route. Choose the best summary – that is, the summary route that includes all addresses in all the subordinate subnets, while including as few extra addresses as is possible.

Table 1 – Three Route Summary Problems

Problem 1 Problem 2 Problem 3
10.100.0.0/16 172.16.207.192/26 192.168.1.100/30
10.102.0.0/16 172.16.205.64/26 192.168.1.80/29
10.104.0.0/16 172.16.206.128/25 192.168.1.72/30
10.101.0.0/16 172.16.204.0/24 192.168.1.112/28
Calculating the Best Summary Route
Answers: Summary Route Practice Set 1
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Vannara Mao

Awesome! Thank you.

toigonbai

Problem 1: 10.96.0.0/12
Problem 2: 172.16.204.0/22
Problem 3: 192.168.1.64/26

e=mc2

Correct ^-^

e=mc2

french habit lol, i mean good answers

TECH-NY

128 64 32 16 8 4 2 1

10.01100|101.00000000.00000000
10.01100|110.00000000.00000000
10.01100|100.00000000.00000000
10.01100|001.00000000.00000000

10.96.0.0/13
————————————

172.16.110011|11
172.16.110011|01
172.16.110011|10
172.16.110011|00

172.16.204.0/22
———————————–

192.168.1.01|100100
192.168.1.01|010000
192.168.1.01|001000
192.168.1.01|101111

192.168.1.64/26

Adams

The actually summarized network is 10.96.0.0/12 instead of 10.96.0.0/13
There is a mistake in conversion of 104 to binary.
0110 0100 -100
0110 0101 -101
0110 0110 -102
0110 1000 -104

lyjo

agreed. also, for anyone who didn’t see the link, the answers post is linked at the bottom of this post.

Bharat

Problem 1- 10.96.0.0/12
Problem 2- 172.16.200.0/21
Problem 3- 192.168.1.64/26

Dinar

Correct Answer. Thank You.

cew

The first list is much easier because all network addresses are 16-bit addresses; I assume (I hope correctly) that in the remaining lists, where for example in one the network addresses are alternately 26-bit, 25-bit, and 24-bit, I will have to leave the lesser amount of bits for individual addresses, and will have to use the full 26-bits for the network addresses — thus I’ll have only 38 bits left for the individual addresses in this case.

lyjo

Hi Cew,
I agree, the first problem was a little easier than the other two (on purpose!). By the way, no sure what you meant about that last comment, about leaving 38 bits for the individual addresses.
I’ll have the answers posted on Friday.
Wendell

[…] (and #CCENT) candidates, here are the answers to that earlier summary route practice set. If you’ve not tried these problems yet, go back, check it out, and come up with the best summary […]

Shiloh

The link: “Check out this post that explains more about route summarization.” = 404 | Page Not Found!

lyjo

We have a few broken links. I’ve got my part time worker going through the entire blog history looking for broken links. I just fixed this one, though. Thanks for the heads up! Should have the rest fixed in the next few weeks.
Wendell

Nada

Good practice

Pavel

PRB 1:10.96.0.0/12
PRB 2:172.16.204.0/22
PRB 3:192.168.1.64/26

lyjo

Pavel,
Thanks for playing! You can see the longer explanation by following the links at the end of the post (above this comment section).
Wendell

Tiger

Can you please help me out in the solution of following question?
“The ISP Company has IPv4 addresses 193.6.128.0/21, 193.6.132.0/21 and 193.6.145.0/24. Because of the address sparing requirement, the company applies superneting mechanism. Calculate the smallest possible list of Supernets for the company ISP?”

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