Thanks Ashish for the reply.
A portal server may choose to implement XMLPortletRequest so that the server returns only the HTML fragment(s) for the portlets whose state has changed in response to invocation of render/action method.
I am bit confused here.
Does it mean, the ajax response can be from more than one portlet , even though the request is targeted to one particular portlet? How the response will be handled in the original portlet which triggered to request ? How it differentiate between the response targeted to it and other portlets ?
May be I have to put my hands in some POC to get clear idea in this.