Hi Siva,
Download the IWSS getting started guide from the following URL.
http://www.trendmicro.com/ftp/documentation/guides/iwss_25_win_en_ag.pdf
Go to page 38.
IWSS support WCCP 2.0 ( cisco protocol for redirecting http requests).
From version 7.2 onwards the WCCP 2.0 is supported in the cisco firewalls.
You can use this feature to redirect the HTTP requests to your IWSS server.
Check for the details in IWSS userguide and Cisco PIX/ASA configuration guide 7.2 for further details
Hope this helps.
-VJ
