Subnetting question

[kimrajsohan]

Hello Guys,

I'm currently studying the CCNA curriculum.

I have a questions regarding subnetting which i cannot figure out.

I have an ip address : 192.165.x.0 too 192.165.64.0.

The questions posed by my instructor:

1)what are the odd numbers for this network, and what would be the mask?

2)What is the network statement for even numbers from 8-15.

Is this a trick question?

Any help or links would be greatly appreciated. A bit stumped.

thx

kim

[ankurbhasin]

Hi Kim,

1) First of all just defining an ip as you have you cannot say what will be the networks and what will be the mask.

The ip range what you have define is 192.165.x.0 to 192.165.64.0 which means 64 networks so the subnet range can be 255.255.192.0 now this range has 64 networks but still if you see the network range will be like 192.165.0.0 - 192.65.63.0, 192.165.64-192.65.127.0 and like this

2) The mask for 8-15 will be 255.255.248.0

HTH

Ankur

[balajitvk · Accepted solution]

i hope u try to mean that ur having a network 192.165.0.0/18.

if u want to say what are odd no. of ips in this subnet you can say which having 1 in the least significant bit of the third octet. If that bit is zero u can take it as even no.

Further if u want to block those(odd) ips alone u can match 192.165.1.0 0.0.254.255 in the access-list.