Ok... My gateway is running COS5.1. I am running the content-filtering proxy (tried in transparent mode and non-transparent mode). I started the protocol filter.
I attempted to block the jpeg file type (simply to test its functionality.)
I went to images.google.com and searched for cars.
jpegs of cars passed through the gateway.
I thought maybe because I'm running the proxy, that may interfere with the functioning of the protocol filter as it relates to web traffic. (and shutting down the filter isn't an option.)
So, I tried to block MSN messenger.
I saw 2 MSN protocols in the protocol filter list, so blocked them both.
MSN messenger continued to work.
Read that established MSN messenger connections may not be blocked, so I rebooted the laptop and MSN messenger continued to work.
Realized that it's now called Live messenger, so thought maybe the protocol changed thus the protocol filter may not identify this traffic.
Finally, I blocked bittorrent.
I successfully downloaded a Fedora ISO using Transmission.
Then I posted this:
Hoping to start a conversation to help me understand how this is supposed to work.
It is likely that I do not understand something or am doing something wrong.
How I thought this would work is… I’d click Block JPEGs on my gateway (proxy or not) and jpegs would not pass through the box.
Any guidance would be appreciated.
What settings are you using?