How to execute a delayed request to the server?

Question

JavaScript

The task is next.
There is a client that must make a GET request to a remote server via http.
At the moment when the server is not responding or not available, it is necessary to display a stub page on the client with the text "Wait, connecting ...". The stub can be stored on the client.
How it is better to implement it?
Restrictions - IE6 only
Thanks in advance.