No subject

ie
192.168.0.12/24 
/24 = 255.255.255.0
 192.168.  0.12
 255.255.255.0    AND
-----------------
 192.168.0.0

So that tells you the network address for 192.168.0.12 is 192.168.0.0

To get the broadcast you NOT the netmask and OR that with the network address.
ie
 NOT 255.255.255.0 = 0.0.0.255

   0.  0.  0.255
 192.168.  0.0    OR
-----------------
 192.168.  0.255
-----------------


Okay so now you know the 
Network address   : 192.168.0.0
Broadcast address : 192.168.0.255
Subnet mask       : 255.255.255.0
(A) Host IP       : 192.168.0.12

When you use an IP network you lose the Network and Broadcast addresses in
each subnet.  You also on older network stacks lose the first and last
subnets.

Here is another eaample

10.10.53.1/22
Network address   : 10.10.52.0
Broadcast address : 10.10.55.255
Subnet mask       : 255.255.252.0
(A) Host IP       : 10.10.53.1

192.168.4.63/30
Network address   : 192.168.4.60
Broadcast address : 192.168.4.63
Subnet mask       : 255.255.255.252
Host IP's         : 192.168.4.60   <-- network
                    192.168.4.61
                    192.168.4.62
                    192.168.4.63  <-- broadcast

This last one is really one C-CLass network subnetted into 64 4-host networks.
I just picked on one subnet.

Having said all that you could just download ipcalc from the net and read the
help output.


HTH

Yours Tony.

/*
 * "The significant problems we face cannot be solved at the 
 * same level of thinking we were at when we created them."
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