Cache only guests with Varnish or Squid in a phpbb2 forum

Just need a proxy cache config (just the config code [login to view URL] in Varnish or [login to view URL] in Squid) that cache guests requests (but at the same time allow guests to login) while loged in users requests are delivered fresh and not cached. Should work with phpbb2. Therefore this can be done using phpbb2 cookies. If I am not wrong phpbb2 cookies have the SID of the user depending on if the user is loged i or not. There is always the ID of the user, if it is -1 then the user is not loged in. I am not absolutely sure about the behaviour of phpbb2 cookies. Varnish is able to to this directly with the cookies (I do not know if this is possible with Squid). If this can be done with Squid instead of Varnish then it is also a good option. Another way to do so would be changing some code in phpbb like for example adding something to the URI so Squid or Varnish can just check the URI instead of a cookie. ## Deliverables 1) Complete and fully-functional working program(s) in executable form as well as complete source code of all work done. 2) Deliverables must be in ready-to-run condition, as follows? (depending on the nature? of the deliverables): a)? For web sites or? other server-side deliverables intended to only ever exist in one place in the Buyer's environment--Deliverables must be installed by the Seller in ready-to-run condition in the Buyer's environment. b) For all others including desktop software or software the buyer intends to distribute: A software? installation package that will install the software in ready-to-run condition on the platform(s) specified in this bid request. 3) All deliverables will be considered "work made for hire" under U.S. Copyright law. Buyer will receive exclusive and complete copyrights to all work purchased. (No GPL, GNU, 3rd party components, etc. unless all copyright ramifications are explained AND AGREED TO by the buyer on the site per the coder's Seller Legal Agreement). ## Platform Any SO Software required (all free): LAMP (Linux, Apache, MySQL, PHP), phpbb2 and a reverse web proxy that could be Varnish-cache or Squid. Only need to deliver the config code [login to view URL] (Varnish) or [login to view URL]