<div dir="ltr">Why is that more convenient for you? The only advantage of your scheme seems to be that you save 28 bytes in the second pass.<br></div><div class="gmail_extra"><br><div class="gmail_quote">On Sat, Feb 20, 2016 at 9:21 PM, Van Gegel <span dir="ltr"><<a href="mailto:torfone@ukr.net" target="_blank">torfone@ukr.net</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div><span>I want to perform DH on the EC25519 and verify the secret using a short fingerprint (32 bits SAS). Typically in this case the commitment needed for preventing MitM by influence the responder's key after originator's key was received.  <br>To be securely the following scheme instead commitment:<br>first exchange parts of the keys (first 224 bits) and then the remaining 32 bits during second pass?<br><br></span><img alt="" style="width:1px;min-height:1px" height="1" width="1">                                                                                                                                                                                                                                                                                                
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