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https becoming http in case of sendRedirect - why?
http://geekexplains.blogspot.jp/2008/06/https-becoming-http-in-case-of.html
What is SSL/TLS offloading?
http://help.fortinet.com/fadc/3-0-0/olh/index.html#page/FortiADC_Handbook/offloading_vs_inspection.html