Possible Ways to Communicate Between iFrame and Parent Page across domains

Question

Please suggest possible techniques to trigger events in parent page from an iFrame. I tried out url Hashing and using window.postMessage techniques but without any success.<

Answer 1

The modern answer to this question is the new cross-document messaging (Web Messaging API)

See Opera's introduction here:

http://dev.opera.com/articles/view/window-postmessage-messagechannel/

Or the specification here: http://www.w3.org/TR/webmessaging/