Anyway to quickly calculate multiples of 8 and 16?

When I'm subnetting 8 and 16 increments, I always get stuck and have to write the increments down. Is there a better way to do this?

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Comments

ande0255

I just write out a line of 2's, and starting above the second 2 in the line I write a 4, and double that for each 2 down the line I go (4, 8, 16, 32, etc). This is my strategy for finding the max number of hosts / subnets during my CCNA exam.

Is that what you're referring to?

bigdogz

Yeah,

Are you trying to translate into binary or hex?

SurferdudeHB

This is when I do a subnet problem and need to find the subnet range

e.g.

Enter the subnet the host 172.28.203.3 255.255.255.240 belongs to

mikeybinec

SurferdudeHB wrote: »

This is when I do a subnet problem and need to find the subnet range

e.g.

Enter the subnet the host 172.28.203.3 255.255.255.240 belongs to

256-240 = 16

0
16
32
48

3 is between 0 and 16 so it belongs to the 0 subnet

As for really big numbers, i.e. lets say your fourth octet was a 150, rough guess what 16 X 9 = or 16 X 8 etc and start from there. You'll still be able t subnet any address within a minute.. Thats what I do