How do you find the number of host in each range problem

SurferdudeHB

Can someone show me how to find the total number of valid host for the subnet range.

16.125.212.0 /22

I was able to figure out,

Network address: 16.125.212.0
Sub mask: 255.255.252.0
Subnets: 64
1st Range of valid hosts: 16.125.212.1 to 16.125.213.254
1022 <-- is this the total number of valid host for this range?

d4nz1g

I would calculate this way:

/32-/22 = 10 (bits available in the host space)

2^10 = Number of hosts on your range.

joelsfood

Don't forget to subtract two for network and broadcast.

SurferdudeHB

d4nz1g wrote: »

I would calculate this way:

/32-/22 = 10 (bits available in the host space)

2^10 = Number of hosts on your range.

Where are you getting the 32 from?

mikeybinec

I've always counted from right to left or left to right. In this case, the hosts go from right to left. So you got 8 already in the 4th block, and then go up to the boundary where your subnet mask resides (in this case, it's the 3rd bit from the right) So 8 bits from the last octet and then 2 from the 3rd makes it 10. 2^10 =1024, then minus 2 for the broadcast and network ID and you have 1022 total hosts

--chris--

SurferdudeHB wrote: »

Where are you getting the 32 from?

The four octet IP address we use in ipv4 =32bits.

Simrid

32 bits would equate to 11111111.11111111.1111111.11111111 as the address is made up of four 8 bit octets.

So as above, simply take the suffix (in this case /22) and minus it from 32 giving you 10.

2^10 = 1024 - 2 = 1022 useable addresses.

I hope this may make sense, if you have any questions, pop me a message.

Jasiono

I highly, and I cannot stress this enough, HIGHLY, recommend watching the CBT nugget videos on subnetting. There are 3 with a total run time of just over an hour.
Watch them once and you will be able to subnet in your head, just like that.

Mooseboost

Jasiono wrote: »

I highly, and I cannot stress this enough, HIGHLY, recommend watching the CBT nugget videos on subnetting. There are 3 with a total run time of just over an hour.
Watch them once and you will be able to subnet in your head, just like that.

This advise will serve you well. Being able to subnet quickly and effectively will help you pass the exam more than anything else.

BigTone

Agreed on the CBT nuggets subnetting method. I went to a Global Knowledge bootcamp a few weeks ago and the instructor pretty much taught it the same way. Another guy at my company went a few weeks prior with a different instructor and he had pages and pages of binary sheets. Don't get me wrong you should know binary but you don't have to kill yourself over it.

SurferdudeHB

I have the CBT Nuggets and will watch them, thx ya'll.