Home > ICND1 – Subnetting 2

ICND1 – Subnetting 2

June 15th, 2017 in ICND1 100-105 Go to comments

[am4show have=’p2;’]

Premium Member: You can test your knowledge with these questions first via this link.

[/am4show]

Note: If you are not sure about Subnetting, please read my Subnetting Made Easy tutorial.

Question 1

[am4show have=’p2;’]Refer to the exhibit. The junior network support staff provided the diagram as a recommended configuration for the first phase of a four-phase network expansion project. The entire network expansion will have over 1000 users on 14 network segments and has been allocated this IP address space:

192.168.1.1 through 192.168.5.255
192.168.100.1 through 198.168.100.255

What are three problems with this design? (Choose three)

subnet1

A – The AREA 1 IP address space is inadequate for the number of users.
B – The AREA 3 IP address space is inadequate for the number of users.
C – AREA 2 could use a mask of /25 to conserve IP address space.
D – The network address space that is provided requires a single network-wide mask.
E – The router-to-router connection is wasting address space.
F – The broadcast domain in AREA 1 is too large for IP to function.

 

Answer: A C E[/am4show]

Explanation

AREA 1 has 500 users but it uses class C which only supports 254 users (from 192.168.1.1 to 192.168.1.254)-> A is correct.

AREA 3 also uses class C and as mentioned above it supports 254 users so it is enough for 200 users -> B is incorrect.

In AREA 2 there are only 60 users < 64 = 26 so we can use a subnet mask which has 6 bits 0 -> /26. Of course we can use larger subnets (like /25) for future expansion -> C is correct.

A large network should never use a single network-wide mask. It should be some different subnet masks to make the network flexible and easy to be summarized -> D is incorrect.

For router-to-router connection we should use a subnet mask of /30 which supports 2 hosts per subnet. This subnet mask is ideal for router-to-router connection -> E is correct.

There is no limit for IP to function if we know how to organize our network -> F is incorrect.

Question 2

[am4show have=’p2;’]Refer to the exhibit. The enterprise has decided to use the network address 172.16.0.0. The network administrator needs to design a classful addressing scheme to accommodate the three subnets, with 30, 40, and 50 hosts, as shown. What subnet mask would accommodate this network?

Net bits Subnet mask total-addresses per subnet
/20 255.255.240.0 4096
/21 255.255.248.0 2048
/22 255.255.252.0 1024
/23 255.255.254.0 512
/24 255.255.255.0 256
/25 255.255.255.128 128
/26 255.255.255.192 64
/27 255.255.255.224 32
/28 255.255.255.240 16
/29 255.255.255.248 8
/30 255.255.255.252 4

 

A. 255.255.255.192
B. 255.255.255.224
C. 255.255.255.240
D. 255.255.255.248

 

Answer: A[/am4show]

Explanation

The maximum number of hosts in this question is 50 hosts so we have to use /26 subnet mask or above.

Question 3

[am4show have=’p2;’]The network manager has requested a 300-workstation expansion of the network. The workstations are to be installed in a single broadcast domain, but each workstation must have its own collision domain. The expansion is to be as cost-effective as possible while still meeting the requirements. Which three items will adequately fulfill the request? (Choose three)

A. one IP subnet with a mask of 255.255.254.0
B. two IP subnets with a mask of 255.255.255.0
C. seven 48-port hubs
D. seven 48-port switches
E. one router interface
F. seven router interfaces

 

Answer: A D E[/am4show]

Explanation

To support 300 workstations in a single broadcast domain, we need to use a subnet mask which supports 512 hosts = 29 -> /23 or 255.255.254.0 in decimal form -> A is correct.

If we use 48-port switches we need 300/48 = 6.25 -> seven 48-port switches are enough because we also need trunking between them -> D is correct.

We only need one router interface and it is connected with one of seven switches -> E is correct.

Question 4

[am4show have=’p2;’]Which router command will configure an interface with the IP address 10.10.80.1/19?

A. router(config-if)# ip address 10.10.80.1/19
B. router(config-if)# ip address 10.10.80.1 255.255.0.0
C. router(config-if)# ip address 10.10.80.1 255.255.255.0
D. router(config-if)# ip address 10.10.80.1 255.255.224.0
E. router(config-if)# ip address 10.10.80.1 255.255.240.0
F. router(config-if)# ip address 10.10.80.1 255.255.255.240

 

Answer: D[/am4show]

Explanation

/19 = 255.255.224.0. The fast way to find out this subnet mask is to remember /16 = 255.255.0.0 and we need 3 more bits 1 for 3rd octet: 1110 0000 which is 224.

Question 5

[am4show have=’p2;’]Refer to the exhibit. A TFTP server has recently been installed in the Atlanta office. The network administrator is located in the NY office and has made a console connection to the NY router. After establishing the connection they are unable to backup the configuration file and IOS of the NY router to the TFTP server. What is the cause of this problem?

IP_Subnet_troubleshooting.jpg

A. The NY router has an incorrect subnet mask.
B. The TFTP server has an incorrect IP address.
C. The TFTP server has an incorrect subnet mask.
D. The network administrator computer has an incorrect IP address.

 

Answer: C[/am4show]

Question 6

[am4show have=’p2;’]Which two statements describe the IP address 10.16.3.65/23? (Choose two)

A. The subnet address is 10.16.3.0 255.255.254.0.
B. The lowest host address in the subnet is 10.16.2.1 255.255.254.0.
C. The last valid host address in the subnet is 10.16.2.254 255.255.254.0
D. The broadcast address of the subnet is 10.16.3.255 255.255.254.0.
E. The network is not subnetted.

 

Answer: B D[/am4show]

Explanation

Increment: 2 (/23 = 11111111.11111111.11111110.00000000 = 255.255.254.0)
Network address: 10.16.2.0 (because 2 = 2 * 1 and 2 < 3)
Broadcast address: 10.16.3.255 (because 2 + 2 – 1 = 3 for the 3rd octet)

-> The lowest (first assignable) host address is 10.16.2.1 and the broadcast address of the subnet is 10.16.3.255 255.255.254.0

Question 7

[am4show have=’p2;’]Refer to the exhibit. The internetwork is using subnets of the address 192.168.1.0 with a subset mask of 255.255.255.224. The routing protocol in use is RIP version 1. Which address could be assigned to the FastEthernet interface on RouterA?

subnet3

A. 192.168.1.31
B. 192.168.1.64
C. 192.168.1.127
D. 192.168.1.190
E. 192.168.1.192

 

Answer: D[/am4show]

Explanation

255.255.255.224 = 1111 1111.1111 1111.1111 1111.1110 0000 (binary form)

Increment: 32

First subnetwork: 192.168.1.0 -> 192.168.1.31 (A is incorrect because 192.168.1.31 is a broadcast address)
Second subnetwork: 192.168.1.32 -> 192.168.1.63
Third subnetwork: 192.168.1.64 -> 192.168.1.95 (B is incorrect because 192.168.1.64 is a network address)
Fourth subnetwork: 192.168.1.96 -> 192.168.1.127 (C is incorrect because 192.168.1.127 is a broadcast address)
Fifth subnetwork: 192.168.1.128 -> 192.168.1.159
Sixth subnetwork: 192.168.1.160 -> 192.168.1.191 (D is correct because 192.168.1.190 is the last assignable host address of this subnetwork)
Seventh subnetwork: 192.168.1.192 -> 192.168.1.224 (E is incorrect because 192.168.1.192 is a network address)

Question 8

[am4show have=’p2;’]A network administrator is connecting PC hosts A and B directly through their Ethernet interfaces as shown in the graphic. Ping attempts between the hosts are unsuccessful. What can be done to provide connectivity between the hosts? (Choose two)

pc_ping_unsuccessful.jpg

A. A crossover cable should be used in place of the straight-through cable.
B. A rollover cable should be used in place of the straight-through cable.
C. The subnet masks should be set to 255.255.255.192
D. A default gateway needs to be set on each host.
E. The hosts must be reconfigured to use private IP addresses for direct connections of this type.
F. The subnet masks should be set to 255.255.255.0

 

Answer: A F[/am4show]

Question 9

[am4show have=’p2;’]If an Ethernet port on a router was assigned an IP address of 172.16.112.1/20, what is the maximum number of hosts allowed on this subnet?

A. 1024
B. 2046
C. 4094
D. 4096
E. 8190

 

Answer: C[/am4show]

Question 10

[am4show have=’p2;’]Refer to the exhibit. After configuring two interfaces on the HQ router, the network administrator notices an error message. What must be done to fix this error?

HQ#configure terminal
HQ(config)# interface fastethernet 0/0
HQ(config-if)# ip address 192.168.1.17 255.255.255.0
HQ(config-if)# no shutdown
HQ(config-if)# interface serial 0/0
HQ(config-if)# ip address 192.168.1.65 255.255.255.240
HQ(config-if)# no shutdown
% 192.168.1.0 overlaps with FastEthernet0/0

A. The serial interface must be configured first.
B. The serial interface must use the address 192.168.1.2
C. The subnet mask of the serial interface should be changed to 255.255.255.0
D. The subnet mask of the FastEthernet interface should be changed to 255.255.255.240
E. The address of the FastEthernet interface should be changed to 192.168.1.66

 

Answer: D[/am4show]

Question 11

[am4show have=’p2;’]Refer to the exhibit. Host B has just been added to the network and must acquire an IP address. Which two addresses are possible addresses that will allow host B to communicate with other devices in the network? (Choose two)

suitable_IP_address.jpg

A. 192.168.10.32
B. 192.168.10.38
C. 192.168.10.46
D. 192.168.10.47
E. 192.168.10.49
F. 192.168.10.51

 

Answer: B C[/am4show]

Explanation

The IP address of host B must be in the range of 192.168.10.32/28 subnet, which ranges from 192.168.10.32 to 192.168.10.47 (Increment: 16), except the IP addresses of 192.168.10.32, 192.168.10.46 (which are the network and broadcast addresses of the subnet), 192.168.10.33, 192.168.10.34 (which have been assigned to the interface’s router and the switch). Therefore there are only two IP addresses of 192.168.10.38 & 192.168.10.46.

Question 12

[am4show have=’p2;’]A network administrator has subnetted the 172.16.0.0 network using a subnet mask of 255.255.255.192. A duplicate IP address of 172.16.2.120 has accidentally been configured on a workstation in the network. The technician must assign this workstation a new IP address within that same subnetwork. Which address should be assigned to the workstation?

A. 172.16.1.80
B. 172.16.2.80
C. 172.16.1.64
D. 172.16.2.64
E. 172.16.2.127
F. 172.16.2.128

 

Answer: B[/am4show]

Question 13

[am4show have=’p2;’]What is the maximum number of bits that can be borrowed to create subnets if a Class B network address is being used?

A. 2
B. 6
C. 8
D. 14
E. 16

 

Answer: D[/am4show]

Question 14

[am4show have=’p2;’]The internetwork shown in the diagram is experiencing network connectivity problems. What is the cause of the problem?

wrong_cable_type.jpg

A. The cabling connecting host A to Switch3 is too long.
B. The address of host B is a broadcast address.
C. The IP address of interface Fa0/0 of Router1 is not a usable address.
D. The cable connecting Switch2 and Switch3 should be a crossover.
E. The IP address of Server 1 is in the wrong subnet.

 

Answer: D[/am4show]

Question 15

[am4show have=’p2;’]What is the subnet address for the IP address 172.19.20.23/28?

A. 172.19.20.0
B. 172.19.20.15
C. 172.19.20.16
D. 172.19.20.20
E. 172.19.20.32

 

Answer: C[/am4show]

Explanation

From the /28 we can find all information we need:

Increment: 16 (/28 = 11111111.11111111.11111111.11110000)
Network address: 172.19.20.16 (because 16 < 23)
Broadcast address: 172.16.20.31 (because 31 = 16 + 16 – 1)

In fact we don’t need to find out the broadcast address because the question only asks about subnet address (network address).

Comments (32) Comments
  1. CCENT Someday
    January 29th, 2014

    If you need help learning to subnet, etc. Here is a video that I used to refresh and/or learn from:

    http://www.youtube.com/watch?v=rs39FWDhzDs

  2. CCENT Someday
    January 31st, 2014

    Anyone,

    I plan on taking exam next week. What other sims/labs did you get besides the OSPF 6 router?

    Thanks in Advance!

  3. Qazi
    February 16th, 2014

    Question no.2, I think none of the answers are correct.
    since, its mentioned clearly that choosen IP is 172.16.0.0 (which comes in Class B with a default mask of /16). More over the design scheme is supposed to be a Classful addressing.

    If you decide to go with /26 network then it will become a Classless Subnetting.
    Even though options are not valid. If those are valid please explain in detail.
    Im about to give exam very soon.

  4. Konan
    March 3rd, 2014

    @Qazi,clasfull in other word means that the address has 3parts,that include:network,subnet,host.In this case 172.16.0.0/26 has 3parts as well.16bits network, 10bits subnet and 6bits host part.Classfull addressing doesnt mean that the mask is the default mask for IP.

  5. Reza
    April 1st, 2014

    In Q3, why do we need to any router? It hasn’t been requested to connect the network to anywhere, has it?

  6. Boner Jamz
    April 12th, 2014

    Hi Reza

    Cisco is a little funny with their wording. You need a router because this is the expansion of a new network onto the existing network. Thus you need a router to route the IP packets.

  7. fez
    April 24th, 2014

    Passed my 100-101 exam today and question 1,2,3,4 were there.. all the best

  8. Manohar Tn
    May 16th, 2014

    Got 986/1000 Marks, {5/16/2014} 50 Questions, Ospf Sim, Security simlet, and Router and switch Simlet Was also there…..All questions From 9tut. and Examcollections…..Now Heading For Icnd2 And Blogging…..

    For Any Help.
    Manohar Tn
    Website: http://www.techlinko.com
    G+ : https://plus.google.com/u/0/+ManoharTN9/

  9. tut
    June 8th, 2014

    guys check this link… Very good video on ip addressing and sub netting

    https://www.youtube.com/watch?v=FrdaCx3R9CM

  10. MO
    August 8th, 2014

    Are these questions included in the real ICD1 exam?

  11. Q
    August 21st, 2014

    Question 3 is correct. Pretty sure the subnet to be used has support for 510 hosts, not 512. The broadcast address and next network address makes it necessary to substract 2 from 512. Doesn’t affect the answer, just a technicality.

  12. Anonymous
    September 15th, 2014

    Hi,can someone Email me.lastest CertExam cant open Dumps.Email:emnico2002@yahoo.com

  13. Gabbie
    October 17th, 2014

    Hi, my exam is this Monday, please send me the latest icnd1 dumps , many thanks! gfedejko@yahoo.com

  14. Ahmed
    March 28th, 2015

    q1 in exam

  15. Ronny
    April 4th, 2015

    Hi Guys , just passed the ICND1 with 100% score, most questions are the same as 9tut. Thanks 9tut!! Question 1 & 3 were there!

  16. Anonymous
    April 15th, 2015

    Hi Guys , just passed the ICND1. most questions are the same as 9tut. Thanks 9tut!! Question 1, 3 & 4 were there!

  17. G-10
    April 26th, 2015

    Q 1, 4 in exam

  18. Anonymous
    July 5th, 2015

    k

  19. 9tut
    July 13th, 2015

    @all: We had to move all the questions and answers out of 9tut. We can only keep the explanation. You can download the questions and answers at: https://mega.co.nz/#!oIdESYbD!yyu33vygrfKPy4rcmcbV6qW2fxINNoTokuDM3CjA_og

  20. Anonymous
    August 29th, 2015

    what happen to the question? no question only explanation?

  21. preety
    November 30th, 2015

    questions plzzz????

  22. Angie
    March 22nd, 2016

    Hi Guys i’m writing ICDN1 next week anyone how wrote this year already,to advise on who was the exam?

  23. shadows
    November 8th, 2016

    Guys, I cant see the Question. It says Question and there is no Question and an Explanation is given ???? Why is this ???

  24. networking by standard
    January 28th, 2017

    This is a very powerful prep website for CCNA exams. I thought I was prepared enough but getting here, I have seen soo many contributions of great minds in CCNA. Thank you all.

  25. jane
    May 17th, 2017

    hi guys,
    can someone send me the dumps according the answers of this site for ICND1 and other material???? please please please. I really neeeeeeeeeeeeeeeed it. heeeeelp me please . I’m sad 🙁 🙁

    my email address is jane_woken52 @ yahoo.com (no spaces before and after @ sign)

    🙁 🙁

  26. mark
    March 2nd, 2018

    question 5. Explain please?

  27. mark
    March 2nd, 2018

    router and tftp server on .96 network. tftp increment is 16 so .96-.111
    i know its a class b address with custome mask, but its not hitting me….?
    thank you, whoever can help!

  28. mark
    March 2nd, 2018

    umm…8 also. 255.255.255.0 means increment of 1 but counting in the 4th octet. I know im forgetting something so basic, but….help pls..

  29. mark
    March 4th, 2018

    got 8, but 5?…

  30. al
    September 19th, 2018

    Thursday, I have an exam for icnd1. Is this dumps still valid?

  31. Tenedos
    June 21st, 2019

    Any new dumps for this section? Anyone take the test recently and seen similar questions?

  32. Shiko
    December 4th, 2019

    Pls could somebody share light to the answer giving on question 10 , how did they come about D as the answer, thanks