help me how to subnet class A, B & C

I can not share the material I have because it is in hard copy form in my books and notes taken in my classroom. If you go online the CCNA class or course curriculum should explain it to you.


I'm sorry but my understanding of why it works or how it works is not good enough for me to explain it to you I just simply know that it works.

i am not telling that your teacher is wrong but conception is wrong as per me!! and i have not gone through 6books with the help of 3teacher(CCNA certified)!...mine was full self study from internet!
and i am able to answer all the question from subnettingquestions.com correctly!

One more question to you...
what you think : for a class B address can i use 255.255.255.240 as a subnet musk?
according to ur previous post answer is no. but i guess you have the actual picture of the network.

255.255.0.0 can not be class A address.
coz for class A First Octet will be in the range 1 to 126
255 is not belongs to this range.

first class a subnet is 255.128.0.0 or /9

first class a subnet is 255.128.0.0 or /9

what does it means?

One more question to you...
what you think : for a class B address can i use 255.255.255.240 as a subnet musk?
according to your previous post answer is no. but i guess you have the actual picture of the network.

To answer this NO you can not use it for a CLASS B

BUT CLASS C NO PROBLEM!

This is what my teachers have show me. It should also be in any good CCNA CISCO textbook.

Look on

www.ciscopress.com

Class A Subnets GO

255.128.0.0 /9
255.192.0.0 /10
255.224.0.0 /11
255.240.0.0 /12
255.248.0.0 /13
255.252.0.0 /14
252.254.0.0 /15
252.255.0.0 /16

CLASS B SUBNETS GO

255.255.128.0 /17
255.255.192.0 /18
255.255.224.0 /19
255.255.240.0 /20
255.255.248.0 /21
255.255.252.0 /22
255.255.254.0 /23
255.255.255.0 /24

THEN Class C goes

255.255.255.128 /25
255.255.255.192 /26
255.255.255.224 /27
255.255.255.240 /28
255.255.255.248 /29
255.255.255.252 /30

/30 or 255.255.255.252 is going to used later by VLSM to conserve both IP address's and subnets [but mostly subnets]. It is used between routers.