×

Warning message

  • Cisco Support Forums is in Read Only mode while the site is being migrated.
  • Cisco Support Forums is in Read Only mode while the site is being migrated.

Exam subnetting question

Answered Question
Mar 17th, 2009
User Badges:

this is Exam question

can someone explain me what is correct answer for this

mant thanks

mahesh



Correct Answer by Harold Ritter about 8 years 5 months ago

Mahesh,


Network A requires at least a /25 to accommodate 120 hosts, which makes B the only option.


As far as link A is concerned, the answer could be D or E, but since D is contiguous with the 3 other links, I would say D is the logical one to pick.


Regards

Correct Answer by Richard Burts about 8 years 5 months ago

Mahesh


From this question network A has 120 hosts. A subnet with /26 mask will support only 62 hosts. So network A needs a /25 mask which will support 126 hosts. So "B" is one of the answers. For link A the correct answer is "D" because the choice in E overlaps the network for Marketing in the drawing.


HTH


Rick

Correct Answer by adamclarkuk_2 about 8 years 5 months ago

Link A just needs 2 IP's one for each router


Link A = 172.16.3.0/30

Usable 172.16.3.1 - 172.16.3.2


172.16.3.40/30 falls into the already used 172.16.3.32/27 network.


Network A needs 120 address, so the closest match here is a /25

Network A = 172.16.3.128/25

Usable 172.16.3.129 - 172.16.3.254


The other 2 /26 networks do not provide enough hosts as a /26 only gives 62 usable IP's.

  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 5 (3 ratings)
Loading.
Correct Answer
adamclarkuk_2 Tue, 03/17/2009 - 07:55
User Badges:
  • Silver, 250 points or more

Link A just needs 2 IP's one for each router


Link A = 172.16.3.0/30

Usable 172.16.3.1 - 172.16.3.2


172.16.3.40/30 falls into the already used 172.16.3.32/27 network.


Network A needs 120 address, so the closest match here is a /25

Network A = 172.16.3.128/25

Usable 172.16.3.129 - 172.16.3.254


The other 2 /26 networks do not provide enough hosts as a /26 only gives 62 usable IP's.

Correct Answer
Richard Burts Tue, 03/17/2009 - 07:55
User Badges:
  • Super Silver, 17500 points or more
  • Hall of Fame,

    Founding Member

  • Cisco Designated VIP,

    2017 LAN, WAN

Mahesh


From this question network A has 120 hosts. A subnet with /26 mask will support only 62 hosts. So network A needs a /25 mask which will support 126 hosts. So "B" is one of the answers. For link A the correct answer is "D" because the choice in E overlaps the network for Marketing in the drawing.


HTH


Rick

Correct Answer
Harold Ritter Tue, 03/17/2009 - 08:03
User Badges:
  • Cisco Employee,

Mahesh,


Network A requires at least a /25 to accommodate 120 hosts, which makes B the only option.


As far as link A is concerned, the answer could be D or E, but since D is contiguous with the 3 other links, I would say D is the logical one to pick.


Regards

Harold Ritter Tue, 03/17/2009 - 08:04
User Badges:
  • Cisco Employee,

Oops. Rick is correct. E is not an option. I check the network map too quickly.


Regards

adamclarkuk_2 Tue, 03/17/2009 - 08:06
User Badges:
  • Silver, 250 points or more

Hi Harold


Does E not fall into the network range hanging off Marketing 172.16.3.32/27 :-s

mahesh18 Tue, 03/17/2009 - 08:22
User Badges:

hi

Many thanks to all again for solving my

questions


sincerely

mahesh

Actions

This Discussion