Sorry that I'm newbie on Proxy Server. I got one question. Below is the a very simple layout network layout:


PC ------> Proxy ----> Internet

I set my default gateway to Proxy. I just wonder:

1. In case I do not configure Proxy setting in client browser, can he access to internet (without additional setting on Proxy)?

2. If question one answer if yes, what is the difference when I configure Proxy setting in client browser. In user point of view, both of them can access internet

Really sorry for stupid question and may be I mix up some concept. Thank you very much!!!

Hi There

Firstly, you need to understand difference between fire-walled connection and proxy.
Your firewall can also be your proxy server, it looks like that is the case on your network.

On the firewall (default gateway) you need to either block direct port 80 ( browsing ) and force your browsers to put in Proxy setting for Internet access.

Or you can use IPTABLES to create Transparent proxy, which will automatically put all browsing through the proxy without users settings.

On the Firewall (gateway) You must add the following rul:

iptables -t nat -A PREROUTING -i $INTIF -p TCP --dport 80 -j REDIRECT --to-port 3128

This will automatically redirect all browsing to your Squid proxy server.

On the Squid configuration, you need to add the configuration for transparent proxy :

http_port 3128 transparent
http_port 3129 intercept

Hope this help