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--></style></head><body bgcolor=white lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-family:Consolas;color:black'>On 9/2/16, 12:09 , "openssl-users on behalf of Salz, Rich" <<a href="mailto:openssl-users-bounces@openssl.org">openssl-users-bounces@openssl.org</a> on behalf of <a href="mailto:rsalz@akamai.com">rsalz@akamai.com</a>> wrote:</span><o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div><div><div><div><div><p class=MsoNormal><o:p> </o:p></p></div><blockquote style='border:none;border-left:solid #B5C4DF 4.5pt;padding:0in 0in 0in 4.0pt;margin-left:3.75pt;margin-right:0in' id="MAC_OUTLOOK_ATTRIBUTION_BLOCKQUOTE"><div><p class=MsoNormal><span style='font-family:Consolas;color:black'>I thought DSA was more secure than RSA? Granted, "I thought" is a newbie</span><o:p></o:p></p></div></blockquote><div><p class=MsoNormal><span style='font-family:Consolas;color:black'>understanding.</span><o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span style='font-family:Consolas;color:black'>This is completely wrong. <o:p></o:p></span></p><p class=MsoNormal><span style='font-family:Consolas;color:black'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-family:Consolas;color:black'><o:p> </o:p></span></p></div><div><p class=MsoNormal style='margin-left:.5in'><b><u><span style='font-family:Consolas;color:#7030A0'>If</span></u></b><b><span style='font-family:Consolas;color:#7030A0'> you have a consistently good source of randomness (in my environment RDRAND counts as such), then DSA is fine, and in theory is stronger than RSA because it relies on a harder mathematical problem. If your source of randomness is questionable – DSA won’t be secure (as Rich said).<o:p></o:p></span></b></p><p class=MsoNormal style='margin-left:.5in'><b><span style='font-family:Consolas;color:#7030A0'><o:p> </o:p></span></b></p><p class=MsoNormal style='margin-left:.5in'><b><span style='font-family:Consolas;color:#7030A0'>Then of course there are the implementation issues – the randomness source may be available, but does the application use it correctly? (I hope that for OpenSSL the answer is “yes”, but I did not check, as I’m using RSA for work-related things, and ECC for fun. </span></b><b><span style='font-family:Wingdings;color:#7030A0'>J</span></b><b><span style='font-family:Consolas;color:#7030A0'>)<o:p></o:p></span></b></p><p class=MsoNormal style='margin-left:.5in'><b><span style='font-family:Consolas;color:#7030A0'><o:p> </o:p></span></b></p><p class=MsoNormal style='margin-left:.5in'><b><span style='font-family:Consolas;color:#7030A0'>Suite B and its follow-up do not include DSA. RSA and ECC only, with a warning to stand by for PQC stuff.<o:p></o:p></span></b></p><p class=MsoNormal style='margin-left:.5in'><b><span style='font-family:Consolas;color:#7030A0'><o:p> </o:p></span></b></p><p class=MsoNormal style='margin-left:.5in'><b><span style='font-family:Consolas;color:#7030A0'>In summary: do what everybody else does – use RSA. </span></b><b><span style='font-family:Wingdings;color:#7030A0'>J</span></b><o:p></o:p></p></div></div></div></div></div></body></html>