Simple proxy server for development

The most frequent pitfall are redirections generated in the application that you will have to rewrite in reverse proxy, the client ip address issue you already said, if using ssl termination maybe the server wants to check client certificate or get user information from it. For proper edge-side reverse proxy caching, application modifications may be needed (adecuate expire headers, unset unneeded cookies, etc.). If you are using windows integrated auth it may be unachievable or a true nightmare

Then you could have tunning issues but I think those will be much easier to resolve. My preferred toolset for this task would be:

• Nginx in the outer layer for virtual host management and location mapping,compression,ssl, access logging
• varnish for caching
• haproxy for request queuing, load balancing and backend checking.
• If you need high availability for you reverse-proxy box(es) keepalived does the job

You simply need to check the authentication feature doc for squid which is available at

http://wiki.squid-cache.org/Features/Authentication

There are a number of authentication methods available with squid and everything is well documented in the above link. Go through it and choose the appropriate one for you.