How Do Large Networks Work

I was wondering how large networks work? Specifically how they get an IP. You see, I know my school has several hundred computers....they connect through some small routers, then into large rackmount switches....and eventually reaching a domain called V. We have several domain servers in the school...and over a terabyte of storage. The network goes online via a Win2k3 Server (v.org) and an OC-3 line. Upon going to one of those "what's my ip" sites, I found that different PC's reported different IPs, and I'm not sure why. Why don't they report the IP of the server, or maybe the switch or router. I'm clueless...

Also, does OC-3 use some sort of modem like a cable/DSL subscriber, or is there some sort of other thing that connects to the internet. And if they use a modem, how do you maintain the settings? Does that work by going to the IP address of the router as well?

A_T

Typically you'll find on larger networks that a network administrator will not use a world routable ip address for every computer system and will instead use something like 10.10.0.xxx or 192.168.0.xxx . These ip address types are not internet routable, so these systems will go through what's called a gateway or proxy server to access the internet. This is also called NAT or Network Address Translation. In addition, because there are some computer systems that the school does not want to allow public access, you may find a non-routable ip address in the classroom, and in the library, you may find something that it does have a publicly accessible ip address.

I'm not going to go indepted about networking, but I hope this brief post helps answer a question or two you had.

For more on networking, google Cisco Networking Academy and check them out. There's alot of good stuff there.


--PuRe

some companies/organisations in USA still hold IP ranges that are routable. A large tire company located in USA, for example, has 2 class B networks. Although its uncommon nowadays, you location may be one of those.
However, diferent pc may report diferent "internet IP" also due to:
a) there is a IP pool and proxy is balancing between them
b) there is More than one proxy at your network, each of them with on "internet ip" address.