https://www.google.co.kr/url?sa=t&source=web&rct=j&url=https://www.itu.int/ITU-D/arb/ARO/2011/CyberSecurityForum-Eg/Docs/Doc11-Sorene_18-12-2011.pptx&ved=0ahUKEwjsv8jc3c_PAhUU82MKHeXuALIQFggZMAA&usg=AFQjCNGzWEx4VBdgLQYrceW-eme4GvjaWw
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