Networking - Subnetting - Discussion
Discussion Forum : Subnetting - Subnetting (Q.No. 4)
4.
What is the maximum number of IP addresses that can be assigned to hosts on a local subnet that uses the 255.255.255.224 subnet mask?
Answer: Option
Explanation:
A /27 (255.255.255.224) is 3 bits on and 5 bits off. This provides 8 subnets, each with 30 hosts. Does it matter if this mask is used with a Class A, B, or C network address? Not at all. The number of host bits would never change.
Discussion:
23 comments Page 2 of 3.
Bijay KC said:
8 years ago
Thank you @Nikhil.
Tara said:
8 years ago
@Seonti.
Here the question is 255.255.255.224.
Convert to binary it is 11111111 11111111 11111111 11100000.
Count nos of 1 ...it is 27.
Here the question is 255.255.255.224.
Convert to binary it is 11111111 11111111 11111111 11100000.
Count nos of 1 ...it is 27.
Nishu Kumar said:
8 years ago
(1)255.255.255.224
128+64+32=224.
2^3 =8, 2^5-2= 32 -2 =30
(2) formula;
Block size = 256 - Actual subnet mask,
=256 -224,
= 32.
128+64+32=224.
2^3 =8, 2^5-2= 32 -2 =30
(2) formula;
Block size = 256 - Actual subnet mask,
=256 -224,
= 32.
Seonti said:
8 years ago
Can anyone explain why it is /27?
Dhananjay said:
8 years ago
Thanks.
Chaithanya said:
8 years ago
24|27 = 3bits on 5 bits off.
2^h-2 h=hostsbits = 5,
32-2 = 30.
Or simple total is 256 so 256-224=30.
2^h-2 h=hostsbits = 5,
32-2 = 30.
Or simple total is 256 so 256-224=30.
Darth vader said:
9 years ago
Convert it to binary:
11111111.11111111.11111111.11100000.
You can't use 1s because they are mask bits, you can use 0s as host bits and they can get values between 0 to 31 (total 32 values).
2 of these 32 host values cannot be used as a host IP because one of them belong to broadcast and the other belong to the network address. There is a formula for this host calculation it is 2^(host bits)-2 For this example it is 2^5 - 2 = 32-2 = 30.
11111111.11111111.11111111.11100000.
You can't use 1s because they are mask bits, you can use 0s as host bits and they can get values between 0 to 31 (total 32 values).
2 of these 32 host values cannot be used as a host IP because one of them belong to broadcast and the other belong to the network address. There is a formula for this host calculation it is 2^(host bits)-2 For this example it is 2^5 - 2 = 32-2 = 30.
Vasundhra said:
9 years ago
Not able to perceive, please explain in an easy way. Is there any formula to calculate subnet mask?
(1)
Sagar said:
9 years ago
Your answer is easy to understand, Thanks @Nikhil.
Narsing said:
9 years ago
Decimal to binary conversion:
255.255.255.255
128 64 32 16 8 4 2 1 2 to the power of 7 = 128.
2 to the power of 6 = 64 .
1 1 1 1 1 1 1 1
128 + 64 + 32 + 16 + 8 + 4 + 2 + 1 = 255.
11111111.11111111.11111111.11111111
255 255 255 255
Eg: 192.168.10.10
192-- 128 64 32 16 8 4 2 1
------> 1 1 0 0 0 0 0 0
168 --> 1 0 1 0 1 0 0 0
10 ---> 0 0 0 0 1 0 1 0
10 ---> 0 0 0 0 1 0 1 0
That means where is the 1 is there will add those numbes, so will get decimal number.
255.255.255.255
128 64 32 16 8 4 2 1 2 to the power of 7 = 128.
2 to the power of 6 = 64 .
1 1 1 1 1 1 1 1
128 + 64 + 32 + 16 + 8 + 4 + 2 + 1 = 255.
11111111.11111111.11111111.11111111
255 255 255 255
Eg: 192.168.10.10
192-- 128 64 32 16 8 4 2 1
------> 1 1 0 0 0 0 0 0
168 --> 1 0 1 0 1 0 0 0
10 ---> 0 0 0 0 1 0 1 0
10 ---> 0 0 0 0 1 0 1 0
That means where is the 1 is there will add those numbes, so will get decimal number.
Post your comments here:
Quick links
Quantitative Aptitude
Verbal (English)
Reasoning
Programming
Interview
Placement Papers