Another way is to count how many bits you add to the right of the original

network. The number of subnets doubles with each bit.

So once again starting with a /16:

add 1 bit (/17) and you have 2 subnets

add 2 bits (/1

and you have 4 subnets

add 3 bits (/19) and you have 8 subnets

etc.

..

..

..

"Kurt" <(E-Mail Removed)> wrote in message

news:(E-Mail Removed)...

> First of all 255.255.0.0 is a /16 network - not a /15. But in its simplest

> terms (since you know how to calculate the number of hosts in a subnet)
you

> can determine the number of subnets by taking the total number of hosts on

> the whole network divided by the number of hosts in each subnet. So if you

> have a class B network, say 172.16.0.0 /16 (subnet mask 255.255.0.0) that

> is a total of 65536 hosts (including network and broadcast). If you break
it

> up into /24 subnets (255.255.255.0) you have 256 hosts per subnet. If you

> then divide the total number of hosts by the number of hosts per subnet

> (65536/256) you get 256 subnets.

>

> "Emiel Lieshout" <(E-Mail Removed)> wrote in message

> news:41a1c1aa$0$767$(E-Mail Removed). nl...

> > Hello,

> >

> > I'm preparing for the 70-297 exam.

> > I know now how to calculate how many hosts there are in a subnet.

> > But i need someone to explane to me how to calculate how many subnet's

> there

> > are for instamce in a 255.255.0.0/15 subnet.

> >

> > I've used the official microsoftpress book, but just don't get it!

> > Maybey one of you can explain or direct me to a site or sent me a word
or

> > pdf-file in wich things are explained.

> >

> > Kind regards,

> >

> > Emiel Lieshout

> >

> >

>

>