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Beyond Blockchain

Beyond Blockchain

These are the slides I used for my presentation at Cybertech Tokyo 2018 on November 30, 2018.

Kenji Saito

November 30, 2018

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  1. What’s the true value of blockchain? I’d say, “it provides

    proof that a digital signature situated in the past is either valid or invalid.” BEYOND-BLOCKCHAIN.ORG 2
  2. The Last Will Test l This is a test to

    see if a particular “blockchain” technology has the true value l Can your “blockchain” be used for saving a person’s last will and testament? l So that you can provide proof for all interested heirs l that the document is kept as-is after digitally signed by the person, l without asking them to “trust” you l Because the private key is no longer private after the person dies, and there generally is a reasonable doubt that a heir or heirs has found the key and rewritten and signed the document with the found key with your cooperation l Many private and consortium ledgers would fail this test l While public ledgers may stop functioning at any time due to external reasons l Don’t buy “blockchain” that fails this test, if you need the true value BEYOND-BLOCKCHAIN.ORG 3

    $VSSFODZDPTUDBOOPUQSPUFDUWBMVFTIJHIFSUIBOUIFJSPXO BEYOND-BLOCKCHAIN.ORG 4 1MBUGPSN #MPDLDIBJO 1SJWBUF-FEHFS ##D #FZPOE#MPDLDIBJO0OF .FUBQIPS /FXTQBQFS.PEFM *OIPVTF.BHB[JOF.PEFM )JTUPSJDBM%PDVNFOU.PEFM 1SPPGPG&YJTUFODF 1SPPGPG8PSL DVSSFODZDPTU /POF 1SPPGPG$POUFYU VOEFSSFTFBSDI 6OJRVFOFTT /BLBNPUP$POTFOTVT #Z[BOUJOF 'BVMU5PMFSBODF )VNBO"HSFFNFOU *NBHF -Can only change when PoW cost is paid -History with the highest cost is the right one Public Space Lucky Number Transaction Local Space -Locally represents relations and ordering -No proof given Transaction Public Space -Evidence is kept at unrelated contexts -If ledger is changed, evidence is left elsewhere Transaction Domain (local space) Domain (local space) Domain (local space) Ledger
  4. Comparison between PoW/(D)PoS and PoCX (Proof of Context) l PoW

    (Proof of Work) l No writing is possible without paying the cost of mathematical lottery (lots of electricity) l Requires Nakamoto Consensus (imperfect and cannot sync with real-time processes) l (D)PoS ((Delegated) Proof of Stake) l Finalizes “the right history” by voting among large native-token holders l Possible “prisoner’s dilemma” (weakness against bribery?) => Both protect by the currency cost (safety depends on the market prices of the currencies) l PoCX (Proof of Context) (under research) l Evidences of transactions are embedded within non-related contexts of randomly selected external domains l Writing is cheap, applications can autonomously continue, but cost of verification needs to be evaluated BEYOND-BLOCKCHAIN.ORG 5
  5. Conclusions l Try “the last will test” before you are

    convinced that some “blockchain” technology is useful for you! l If your problem is not transformable into the last will test, you would not need “blockchain” anyway l One way or the other, this will save a lot of your time and money ;) l We are building technology that can pass the test, assuring autonomy of applications at the same time l If you are interested, please join! l https://github.com/beyond-blockchain BEYOND-BLOCKCHAIN.ORG 6