sorry another wildcard question.......

hodgey87

hi all,

sorry about this but its another wildcard question.

i have a network with an ip address of 172.16.0.0 and a subnet mask of 255.255.248.0

i have subnetted this and my first subnet that i have is:

172.16.8.0 first host of 172.16.8.1 - 172.16.15.254

now i need to create a wildcard mask so that it permits only half of the addresses and not the others

i know that the wildcard mask would be 0.0.7.255 for the whole network but how would i work out the wildcard mask for just half the addresses

any help would really be appreciated

thanks

cisco_trooper

0.0.3.255

write it in binary and you'll see why

hodgey87

ok cisco_trooper i think i have it can i just explain to you what i understand from this

i originally had an ip address of 172.16.8.1 for example which was

1.0.1.0.1.1.0.0 0.0.0.1.0.0.0.0 0.0.0.0.1.0.0.0 0.0.0.0.0.0.0.1

for the whole network i focused on the 3rd octet and this was an 8 so the block size was 8 however you have to minus 1 so the block size would be 7

for half the network i have have the block size of 8 for the whole network so half would be 4 but you have to minus 1 so the blocks size will be 3

I think i have understood but not explained this very well

please correct me if this is all wrong