At 01:55 AM 10/1/96 +2600, you wrote:
[snip]
>More or less. Subnetting uses a subnet mask. Any bit that is on in
>the mask is a network bit. If the bit in the mask is off, the
>bit belongs to a host part of the address. In your case above,
>using a mask of 192 means that the first two bits are the subnet,
>the rest are hosts. The first two bits give 4 networks (not two).
>So in this case, you can use all four!
Careful here. According to the RFC he had it dead on. You cannot use
subnet 0 (extra bits of network mask are all zeroes) or the broadcast
subnet (extra bits of network mask are all ones). However, many of todays
devices let you get away with using them.
In ciscos you can specify 'ip subnet-zero' will permit you to use the zero
and broadcast networks. Suns (sunos 4.1.x and Solaris) allow it. Linux
allows it. Some older 3com routers I worked on would allow you to use the
subnet 0 but not the broadcast network.
In general, if you are not sure what will be connected to the network or
you know that some OLD equipment will be connected then it is better to not
try to use them. If you do know that it will all be fairly recent products
then you can go ahead and use them.
GK
>If you want two subnets, use a different subnet mask, and remember,
>the net bit can be anywhere, so you can divide it into two parts,
>as long as it's a power of two. This way, you don't lose that
>many numbers!
>
>--
> ) _) Harry Feltsadas __
> / / mailto:harry @
fdc .
nl __ __(_ )
> _ ) _ _/ http://www.fdc.nl/~harry ' | '/ /
> __/ __/ __/ < A Red Goose and a Red Duck > ___/ ___/
>
>
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