Funny! I had to answer a similar question recently!! I was asked to evaluate between iPlanet and ATG.. and I'll quote straight from the email I wrote:
If (server = iPlanet) and (language = PHP)
Then it can handle PHP itself - we do not need Apache. iPlanet = competitor of Apache as well as ATG, all rolled into one, for big bang $$$. iPlanet is actually quite a super server if one can afford it, which people cannot normally do.
Else If (server = ATG) and (language = PHP)
Then we will need Apache because ATG is only a J2EE server, not a "complete" webserver. If the whole website was only a J2EE based site (JSP/Servlets/..) then ATG can handle it all by itself. BUT if we go with PHP/PERL/etc then ATG needs to be alongside Apache. ATG, like other J2EE servers can be set up in either a stand alone mode or to run along with Apache. So Apache handles/serves all the usual files itself (HTML, PHP etc) but for all the JSP/Servlets stuff, it pulls in ATG.
Else If (server = any) and (language = JSP)
Both iPlanet as well as ATG alsone can handle it. Apache can handle it with help from any J2EE server. Recommended though: Resin (www.caucho.com) or OrionServer (www.orion.com)
Else If (server = any) and (language = PHP)
Apache! Apache! Apache!
End If
Hope that answers your question?
Cheers
Shanx
