I can walk you through the basic steps (some don't relate to the OSI layers though);
- users types in
www.google.com- browser is configured for PROXY or PAC file?
- if PAC file the JavaScript is evaluated and a decision returned
- if PROXY the browser send the entire request to the PROXY server
- else the browser attempts to resolve the IP address of the host
- the machine attempts to open a TCP socket to HTTP (TCP/80) with that host
- the browser exchanges greetings with the server per the HTTP/1.0 or HTTP/1.1 spec
- the browser displays the data to the user
Cheers!
