How to design a simple proxy server that reads configuration files and blocks some websites?

Hi i was thinking to build simple proxy server for my flat so that our flatmates are not spending hours and hours downloading stuff, streaming on youtube and eating all the bandwidth. How am i going to build a simple proxy server so that i can restrict other flatmates going on some particular sites. I was thinking to use some kind configurable file and list the name of the site that are going to be restricted. the question is, where do i start form ? can anyone help me to generate an algorithm to build a simple server ?

Th开发者_StackOverflow中文版anks

You would probably be better off using OpenDNS and having SQUID Proxy Server configured on the system from which you are sharing internet to other systems, rather than implementing your own solution as it is a very complex task to implement a proxy server which provides a decent level of security.