We have Windows XP SP3 clients. Their IE is configured to use an auto.pac file which will determine if a website is internal or external. The PAC is located at http:\\server1\auto.pac
If the server is external, there are HTTP proxies that the request will get sent to, let's name it Proxy1.
If I ran Wireshark on an XP machine, is this the result I should expect to see when attempting to browse an external site (www.google.com
1. DNS resolution for server1
2. Contact server1's IP
3. After reading the auto.pac and realising Google is externally hosted, a request for DNS resolution of Proxy1
3. Contact Proxy1's IP
4. Proxy1 sends authentication request
5. User returns details
6. Contact Proxy1's IP again with an HTTP GET
Also, how can I work out what authentication mechanism the Proxy1 device is using? I have used Wireshark and can see this:
"Proxy authenticate: NTML .. Proxy Authenticate: BASIC realm="proxy".."
So is it using NTLM or Basic?
I would like to know what sort of authentication mechanism these proxies use.