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cidr question

thisisalex02

well i can subnet and all that good stuff but im having a tough time understand these type of questions..

how many /21 are in a /20

or how many /23 in a /20

i seem confused.. anyone point me in the right direction

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Comments

thisisalex02

BUMP

lol

mikej412

power of 2s

number of bits difference

.... you do the math

romain

Convert in binary, it will be easier...

steve-o87

Im surprised that anyone at CCNP level cant do this...

thisisalex02

thats it ? ? wow that was easy

romain

steve-o87 wrote:

Im surprised that anyone at CCNP level cant do this...

The goal is not to provide the solution everytime but to tell how to resolve...
It's the CCNP forum and this is CCNA level question...

thisisalex02

funny how i never got one of those on my ccna.. yet more complex subnetting. i just didnt understand question.. this is a forum.. this is the purpose "TO INFORM".. this morning i passed COMP, but i guess im dumb

Trailerisf

Purpose of a forum is not to inform, but rather DISCUSS.

thisisalex02

Question has been answered

THREAD CLOSED !

mikej412

thisisalex02 wrote:

THREAD CLOSED !

You can do that?

For the Cisco Academy Courseware, it was buried in a flash animation video on the Cisco Press Academy CCNA Companion book CDROM, so it wasn't an obvious part of the CCNA.

Some people may have tripped over similar questions (without the slash notation) on the subnetting questions website.

Okay -- before you permanently close the thread.... what was it? My powers of 2 comment? Or niamor's do the binary (which is always the ultimate answer)?

romain

mikej412 wrote:

Okay -- before you permanently close the thread.... what was it? My powers of 2 comment? Or niamor's do the binary (which is always the ultimate answer)?

Should be mine...

mikej412

niamor wrote:

Should be mine...

Hey -- I thought about tacking on "or you can convert to binary...." to my post.

And I did/do concede you had the ultimate answer to any subnetting/supernetting question!

When in doubt -- do the binary! Once you understand what is going on -- then the tips and tricks are fine.

thisisalex02

your # bit difference and powers of two comment nailed it. I never hit that in my studies. ok time to hit up cit and bcran before the month is over. Thanks mike.. tell ur cats i said hello