{"id":58,"date":"2005-03-21T09:59:25","date_gmt":"2005-03-21T14:59:25","guid":{"rendered":"http:\/\/stein.everybody.org\/journal\/posts\/secret-verifiable-dated-information\/"},"modified":"2013-04-27T14:19:01","modified_gmt":"2013-04-27T18:19:01","slug":"secret-verifiable-dated-information","status":"publish","type":"post","link":"https:\/\/jeremystein.com\/journal\/secret-verifiable-dated-information\/","title":{"rendered":"Secret Verifiable Dated Information"},"content":{"rendered":"<p>I&#8217;ve been puzzling over how a person could prove that he had certain information at some date in the past, without publishing it until later.  In the movie <a href=\"http:\/\/www.imdb.com\/title\/tt0110932\/\">Quiz Show<\/a>, one of the contestants sent the answers to himself in registered mail to be able to later prove that the show had been rigged.  (<a href=\"http:\/\/historymatters.gmu.edu\/d\/6555\/\" title=\"Testimony of James Snodgrass\">This really happened<\/a>.)  That seems like a fairly clever way, assuming the USPS is rigorous in <a href=\"http:\/\/pe.usps.com\/Archive\/HTML\/DMMArchive0810\/S911.htm\">ensuring that the mail is sealed<\/a>.  I wonder whether it would be possible to send an envelope with registered mail and then insert a paper after it was received.<\/p>\n<p>What other way is there to prove that information existed at a certain time in the past?  It seems like you&#8217;d have to have some trusted authority for dating information.  The postmark date is the authority in the above example.  How about data encrypted with <a href=\"http:\/\/www.gnupg.org\/\">pgp<\/a> and cached by <a href=\"http:\/\/www.archive.org\/\">The Internet Archive<\/a>?  Any other suggestions?<\/p>\n","protected":false},"excerpt":{"rendered":"<p>I&#8217;ve been puzzling over how a person could prove that he had certain information at some date in the past, without publishing it until later. In the movie Quiz Show, one of the contestants sent the answers to himself in registered mail to be able to later prove that the show had been rigged. (This [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5],"tags":[],"class_list":["post-58","post","type-post","status-publish","format-standard","hentry","category-geek"],"_links":{"self":[{"href":"https:\/\/jeremystein.com\/journal\/wp-json\/wp\/v2\/posts\/58","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/jeremystein.com\/journal\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/jeremystein.com\/journal\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/jeremystein.com\/journal\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/jeremystein.com\/journal\/wp-json\/wp\/v2\/comments?post=58"}],"version-history":[{"count":1,"href":"https:\/\/jeremystein.com\/journal\/wp-json\/wp\/v2\/posts\/58\/revisions"}],"predecessor-version":[{"id":327,"href":"https:\/\/jeremystein.com\/journal\/wp-json\/wp\/v2\/posts\/58\/revisions\/327"}],"wp:attachment":[{"href":"https:\/\/jeremystein.com\/journal\/wp-json\/wp\/v2\/media?parent=58"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/jeremystein.com\/journal\/wp-json\/wp\/v2\/categories?post=58"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/jeremystein.com\/journal\/wp-json\/wp\/v2\/tags?post=58"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}