Access-list and Blocksizes

Sorry, but i have one more question!

When i want to block the range between 172.16.8.0 and 172.16.32.0
what is the Blocksize in the access-list?

Ist it 0.0.55.255 ?

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Comments

seth223uk

to block a range u have to block in binary ranges etc 8 16 32 to block 172.16.16.0 to 172.16.32.0 draw out the binanry chart for 16 to 32 and see which columns are in common in this case the ones that are in comon make up the wildcard mask ie 0.0.15.255 is the mask for this im pretty sure to block that range of subnets for 16 - 32 on that network number

Cypunk

Once again, thank you Seth!

so that mean, when i want to block i.e networks 172.16.8.0 up to 172.16.32.0, i have to assign two access-lists?

The first one should be the address 172.16.8.0 0.0.7.255
And the second address 172.16.16.0 0.0.15.255

(Why is there no confused-Emoticon on the left side?)

muthuvelk

hi,

U want to block N/Ws between 172.16.8.0 and 172.16.32.0.Right..
Totally u want to block 25 n/ws.So u have to use Blocksize of 32,Just > than 25 (because we can use 64,32,16,8 and 4 ).Here 25 N/Ws u have to block.So Wildcard will be 0.0.31.255.

It is sure.

chalaak

hey there...

ok am confused now......arent we trying to block 172.16.8.0 to 172.16.32.0.....seth u answered 16-32..but the question requires u to block from 8-32 does it not?...so shudnt it be...0.0.24.255?