Subnetting Question
Steadfast Girl
Registered Users Posts: 4 ■□□□□□□□□□
in Network+
How many subnets and hosts per subnet can you get from the network 174.20.0.0/23 Remember for host part at least 2 bits are required?
Solve this question please and tell me the complete method ...
Thanks in advance
Solve this question please and tell me the complete method ...
Thanks in advance
Comments
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fadhil
Member Posts: 200
there are 128 subnets and 510 hosts from that network.
to get number of hosts
from /23 it means that 23 bits are on while others are off. so take number of bits which are off.
for there are 9 bits which are off
then 2^9 -2 =510 number of hosts.
for number of subnets
since it class B its default is /16.but according to the question is /23.
take 23-16=7
hence to get subnets =2^7 =128 -
swild
Member Posts: 828
its a 32 bit address with 23 (/23) bits for the network leaving 9 bits for the host.
The mask would be written in binary like this:
11111111.11111111.11111110.00000000
Ones being "on" and the zeros being the "off" bits. -
gadav478
Member Posts: 374 ■■■□□□□□□□
yeah bro that method is smoking fast... bookmarking this now.Goals for 2015: CCNP -
rphann
Member Posts: 76 ■■□□□□□□□□
The answer is: 510 hosts per subnet and 128 subnets.
255.255.254.0 = subnet mask
11111111.11111111.11111110.00000000
Determine the hosts:
Formula: (2^h)-2=
(2^9)-2=510
Note: count the zeros for the hosts (h)
Determine the subnet:
Formula: 2^s=
(2^7)=128
Note: count the ones in the third octet. -
Irfanshafiq
Registered Users Posts: 1 ■□□□□□□□□□
Good Day to All...!!!!
What will we say about the class of this IP
174.20.0.0/23
Either it is a Class B IP or example of Class less IP...
Looking for expert comments.
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fadhil
Member Posts: 200
Irfanshafiq wrote: »Good Day to All...!!!!
What will we say about the class of this IP
174.20.0.0/23
Either it is a Class B IP or example of Class less IP...
Looking for expert comments.
that is class B ip address since class B range from 128 to 191 and class C range from 192 to 223 -
KenC
Member Posts: 131
that is class B ip address since class B range from 128 to 191 and class C range from 192 to 223
I think this is considered a CIDR address (classless) because the default subnet mask of 255.255.0.0 for class B is not being used. -
NetworkVeteran
Member Posts: 2,338 ■■■■■■■■□□
Steadfast Girl wrote: »How many subnets and hosts per subnet can you get from the network 174.20.0.0/23 Remember for host part at least 2 bits are required?
Solve this question please and tell me the complete method ...
Thanks in advance
A /24 has 256 addresses. A /23 must has one bit more (twice as many addresses), and 256x2 = 512.
You generally subtract the all-zeroes and all-ones host addresses, leaving 510 host addresses.
174.20.x.x is Class B (16 network bits), so there are 23-16=7 subnet bits.
2^7 = 128 subnets total. -
NetworkVeteran
Member Posts: 2,338 ■■■■■■■■□□
Subnetting predates and does not require CIDR. In this case, there are 16 network bits, 7 subnet bits, and 9 host bits. In fact, answering "How many subnets?" with a concrete number--as is typical--obligated us to make the classful assumption that there are 16 network bits!I think this is considered a CIDR address (classless) because the default subnet mask of 255.255.0.0 for class B is not being used. -
KenC
Member Posts: 131
I'm a little bit confused about this - will have to revisit the books.
So is CIDR got to do with dealing with public IP addresses or something?
