Preventing iframe caching in browser

Question

How do you prevent Firefox and Safari from caching iframe content?

I have a simple webpage with an iframe to a page on a different site. Both the outer page and the

Answer 1

To get the iframe to always load fresh content, add the current Unix timestamp to the end of the GET parameters. The browser then sees it as a 'different' request and will seek new content.

In Javascript, it might look like:

frames['my_iframe'].location.href='load_iframe_content.php?group_ID=' + group_ID + '×tamp=' + timestamp;