There is something like 64 thousand ip addresses in the private 192.168.x.x range. (192.168.0.0 - 192.168.255.255)
The subnet mask will determine the range of IP addresses that will be in your local network. Your local network being the computers/devices you have direct access to send data without needing to be handled through a router. The common and default subnet mask that is used in a SOHO network and on a Private C class block is 255.255.255.0. This will allow for a total of 254 hosts. This is the default setting for most consumer routers from Linksys, D-link, Netgear, etc. If computerA had an ip address of 192.168.0.12 and a subnet mask of 255.255.255.0 it would be able to communicate with the network range of 192.168.0.1-192.168.0.254. If computerB had an IP of 192.168.9.5 and the same subnet the valid network range would be 192.168.9.1-192.168.9.254. A ping from computerA would not reach computerB or vice versa because they are on two different networks. Hopefully this crude example shows how the subnet mask determines the ip range; especially, how that particular subnet mask would restrict your ip range to whichever block you choose in the third set of numbers. How did you need to apply this knowledge?? Are you configuring a router or small network in your home?? DHSinclair <[EMAIL PROTECTED]> wrote: OK, I now use what I read is the Class C private IP address series. I use 192.168.2xx.x. I am told that my sub-net mask should be 255.255.255.0. If this is true, then should not my chosen 3rd quartile of "2xx" really be a value 0? Or, does it really mean that my chosen 3rd quartile is somehow ignored? Yes, I do recall discussion about this last year, but back then I was using the Class A private IP series......... :) Thank you for any/all de-mystification. Best, Duncan
