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<body><div>On Wed, Dec 10, 2014, at 19:56, Mike Hearn wrote:<br></div>
<blockquote type="cite"><div dir="ltr"><div>I would like to hear opinions on the value of deniability in OTR like protocols.<br></div>
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<div>From a privacy perspective the rationale is fairly clear.<br></div>
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<div class="signature">The practical value of deniability at the protocol level would be much higher if it was deeply integrated into the user interface of (commonly used) client software.<br></div>
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<div class="signature">The absence of cryptographic proof of who originated the message means little if clients by default keep a fixed record of who sent the message and when. If one of the parties becomes compromised this record will be sufficient proof to anyone not understanding the intricacies of the protocol. While such a record could be altered, it would require special tools to edit the clients database, etc, which is not very convincing.<br></div>
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<div class="signature">Clients implementing protocols with deniability should surface this all the way up to the UI and make the conversation completely editable in a trivial manner. If you can show that simply swiping a message on your phone attributes it to someone else that becomes a very powerful way of showing the lack of clear attribution in the underlying protocol.<br></div>
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<div class="signature">One cannot, of course, prevent the other party from using a client without editable history but if widely implemented there is a good chance the average user will have it and a compromise at a later time will only yield an uncertain history of the communication.<br></div>
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<div class="signature">An alternative is to never keep a history in the client which is definitely the best approach for very sensitive conversations but for day to day messaging people expect to have at least a short history for reference and context.<br></div>
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