Hi Vedha,
As mentioned by Radek, there is no mechanism in HTTP to "cancel a request". Will the request the user does on SECOND have a side-effect? If not, maybe you don't need to worry about canceling it; the user clicks on a link taking her from SECOND to FIRST, the browser closes the HTTP connection started by the Ajax request, and when the server finishes its processing, it tries to write an answer, but notices the connection was closed, so logs an exception on the server, but it's all fine from the user's perspective.
Alex
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