What is a "subnet mask"?

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Best explanation I've ever seen on the subject!
I just now went from "what the heck is that all about, let's just use 255.255.255.0" to "AHA.. Now I get it !!" (but will for now still use 255.255.255.0 :-) )...
Thank you so much for clearing this up ;-)

can u help, im tryin to set upmy xbox live and its askin me 4 my subnet mask .how do i find this

I'd need to know a lot more about your network setup, but 95% chance it's 255.255.255.0.

Good. All the other places confused me

according to the tech guy at verizon my "ppp subnet mask' has been changed to all 255's by what he refered to as a fragment of some sort of spyware, now my computer apparently tries to log onto itself and after a few minutes my internet just crawls because of the lag. is there any way i can change that subnet mask back to another figure, the other two subnets are set to 255.255.0.0.
any help would be appreciated

i like this site

tell me how to devise subnet? thanks

What is a subnet mask. How we define it and whz it purpose in network.

Hi. I am supposedly on a two computer network in my home, but have a subnet mask address. Does this mean there is at least one other computer involved? I ask because I believe that there is another one involved in a situation where my internet activities are actually being monitored from a computer outside my home.

Your explanation was the only one of the ones on the internet that I could understand. Thank you for using the analogy.

There's always a subnet mask, so seeing one doesn't really tell you anyting about the presence of any other computers on the network.

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