further to yesterday's testing, we did some more today as follows: first i exposed a web server to the world (forwarded from my firewall to an internal machine running the server). my friend in china could attach and view my web pages. then i forwarded port 6667 -> 80 so that it looked to the world like the web server was operating on port 6667. my friend could still attach with a web browser. mirc could not attach on either port 80 or 6667, but internet exporer could on both. so i can say conclusively that port 6667 is not blocked by the firewall at the school my friend is at.
