Well, you have to understand what an IP is: An IP is just an unique number in the world that identifies your computer on the internet and is used to connect two (or more) computers. So each time you visit a web page (for example) your computer is sending the IP to the server so it can send the page to you.
From that point of view, IPs are a public thing and there's nothing wrong with people knowing your IP. However if you want to hide it, you can use a proxy, as back_m said. A proxy is just a computer/program that you connect to it (it knows your IP) but it connects to the web site (or whatever) you really want to connect, so the web site only knows the IP of the proxy. That way, you can hide your IP.
About what your school have, it may be a proxy, or a router or both things. Anyway, the feature you're describing that it does, is just like a firewall. It blocks some connections, but does not prevent someone of knowing the IP (<- this may be done with the router or proxy, not the firewall).
Sumarizing:
quote:
Originally posted by pr0xy
Just a prØxy ?, or does it hae a certain name.
A proxy is the name. Now you have to google and search a good one.
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