Blockchain 区块链.ppt

BLOCKCHAIN by邓斌斌 Whatisblockchain trade 默克尔树 Eachtransactioninthesetthatmakesupablockisfedthroughaprogramthatcreatesanencryptedcodeknownasthehashvalue HashvaluesarefurthercombinedinasystemknownasaMerkleTree Theresultofallthishashinggoesintotheblock sheader alongwithahashofthepreviousblock sheaderandatime stamp Theheaderthenbecomespartofacryptographicpuzzlesolvedbymanipulatinganumbercalledthenonce Onceasolutionisfoundthenewblockisaddedtotheblockchain 代码加密 时间戳 加密 Numberonce Whataretheapplicationofblockchain DistributionShoppingTrustInternetTransactionSecurity 分布式账本 添加幻灯片标题 1 decentralization 去中心化 Ifyou reahackerYouwillAttack BANK Blockchain 欺诈 Traditional dataglobalization Blockchain Security Thankyou BlackTechnologyinAmericanelection 毛承蔚 Paylessbutgainmore 300million 400million Thankstobigdata hiahiahia NateSilver In2008 Itpredicted49ofthe50stateselectionscorrectly In2012 Itpredictedall50stateselectionscorrectly Then Proposed bigdataresearchanddevelopmentinitiative Investmorethan200milliondollars Improvecollection storage retention management analysisandThecoretechnologiesneededtosharevastamountsofdata So now Therearemorethan772datacentersisrunning Withmorethan70 000servers Andabout7millioncomputerterminals GOODJOB whoisthenext Aelectionwithstrongbigdatagene Inthiselection thetechnologyteamthatservedMrsClinton selectionhasmorethan50people theequivalentofasmallsiliconvalleytechstart up HillaryClinton 240million PageRank 李存益 PageRank Awonderfulwaytoidentifythelevelandimportanceofawepage Thebasicalgorithm 1 everywebpagewillgetthesamePageRankatfirst2 Executethefollowingcycle EachpageassignsitscurrentPageRankequallytotheoutwardlinksonthispage sothateachlinkgetsthecorrespondingPageRank Foreachcycle thenewPageRankisobtainedbysummationofallthePageRankthatispassedininwardlinksofthispage 3 Afterseveralcycle thePageRankofeverywebpagewon tchangeanymore AndthemorehigherthePageRank themoreimportantthewebpage SimplifiedAlgorithm L thenumberofoutwardliknksPR thePageRankinthiscycleq Dampingfactor theprobabilitythatauserreachesawebpageandcontinuestobrowsebackwardsatanytime Advantage Itisastaticalgorithmwhichisindependentofthequery AndthePageRankofallwebpagesisobtainedbyofflinecalculation Iteffectivelyreducetheamountofcomputationinonlinequery greatlyreducethequeryresponsetime disadvantage People squeriesa