ipconfig question

  • Thread starter Thread starter Dan
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Dan

How come it's possible to have a class A IP address
and a class C subnet?

example, when I run an ipconfig I see the following:
IP address 10.36.189.114
Subnet Mask 255.255.255.0

shouldn't the subnet read 255.0.0.0?

I am on a network at work, but could someone please explain this to me?
 
if you don't understand it, you shouldn't be running
ipconfig! the class c subnet mask returns a subnet of
10.36.189.1-254. that means you can have 254 clients in
this ip subnet. if you use a class b mask(255.255.0.0)
then you can have 10.36.1.1-254; 10.36.2.1-254, etc to
10.36.254.1-254. you do the math and find out it's a
BUNCH of clients. if you use a class A subnet mask
(255.0.0.0) then it's 10.1.1.1-254; 10.2.1.1-254 etc and
then 10.1.2.1-254; 10.1.3.1-254...which makes it a WHOLE
BUNCH MORE clients. The nature of the ip address numbers
tell you NOTHING about it's class. Class is defined
entirely by the subnet mask.
 
Well, technically your half right. You ARE on a Class A
network...sorta. If you are on an internal network, the
network admin more than likely has a NAT system set up.
With that, the netadmin can have set up the internal IP's
separate from the outside world. Standard internal IP
addressing is either 10.x.x.x, 172.16.x.x, or 192.168.x.x.
Then, the netadmin uses whatever subnet needed...in this
case, you more than likely have a single subnet, aka ur
entire network on the same network.

Now, NAT comes in when you want to reach out to the
Internet. The NAT server, which is either an actual
server, your firewall, or a gateway router, takes your IP
of say 10.65.26.132 and translates that into an EXTERNAL
IP address...which may be 65.68.7.16. The reason to do
this is two-fold: one is so that way, you can use a
limited number of IP address for a much large group of
users; hense you may have 25 people on your internal
network, yet only two external IP address. The other
benefit is security, and a hacker won't be able to
identify which workstation or what IP setup is in use, due
to the external IP address.

Sorry its a lil lengthy, but thats the jist of it.
 
Class is NOT determined by the subnet mask, but by the first number in the
IP address.

Your network is simply subnetting the network to control the number of IP
addresses that are available.
 
Is there a way to verify what the IP/subnet mask of the router,
firewall, or proxy server might be from a regular user on the subnet?
Some type of DOS or Unix command?
 
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