In dire need of help with subnetting

sq876

iam kinda new to this subnetting field and iam having some problems with subnetting this IP address 170.70.0.0 i know the default mask is 255.255.0.0 seeing that its a class b address now iam supposed to borrow 8 bits to create a new subnet therefore the new mask would be 255.255.255.0 and the first useable subnet would be 170.70.0.0 now the trouble iam having is i don't know what my step size should be and first usable range of hosts and broadcast address iam completely stuck here can someone please shed some light on what iam missing here

HP_Guy

I'll take a stab, although I am only studying for CCENT currently...

Looks like an easy one in that there are no 'interesting octets' - it's all 255s and 0s. The whole of your 3rd octet is used for the subnet and the 4th for the hosts. So as you say the first useable subnet is 170.70.0.0, useable hosts 170.70.0.1-170.70.0.254 (255 for the broadcast). Next subnet is 170.70.1.0 hosts 170.70.1.1 - 170.70.1.254 (255 for broadcast).

Then 170.70.2.0, then 170.70.3.0 and so on and so on.

Andy

sq876

ok im getting the picture so for the next subnet 170.70.2.0 my usable range of host would be 170.70.2.1-170.7.2.254

FloOz

Yes you are correct

PCSPreston

Correct!

This may help you

Subnetting Without Tears

sq876

thank you guys you helped me a lot