XMLHttpRequest - It is used for making requests to the
non-Ajax pages. It supports all kind of HTTP request type.
IFrame - It can make requests using both POST and
GET methods. It supports every modern
browsers. It supports asynchronous file uploads
Cookies - In spite of implementation difference
among browsers it supports large number of browsers
The interface is much responsive,
instead of the whole page, a section of the page is transferred at a time.
Waiting time is reduced
Traffic to and from the server is reduced.
XMLHttpRequest -In the older version of IE (5 & 6)
ActiveX to be enabled, this feature is
available in new browsers and latest version of few.
IFrame - Requests have to be asynchronous. The design
of the Server pages must be compatible with IFrame requests There is
an implementation difference among different
browsers. Unnecessary history records can be left on the history record of
the browser. Request size is increased due to the fact that data is
Cookies - It prohibits no synchronous requests, it does
not cope with large
requests/results The server pages requires to be designed to work with